WordPress.com



Course 1 Unit 4Multiply and Divide FractionsName: ___________________Lesson 4-1: Estimate Products of FractionsTo multiply fractions or find a fraction of a #:Step 1: _________________ by the ______________________________. Step 2: _________________ by the ______________________________. Example 1: Estimate 14 x 13.Method 1: Use a Model1. Divide the bar into 4 sections (total is 12)2. Each section is 14 of 12, or 3.Method 2: Use compatible numbers.13 ≈ ____________ ÷ 4 = ______So 14 x 13 is about ______.Example 2:Estimate 25 of 11.Step 1: 11 ≈ ______Step 2: Divide by the denominator:______ ÷ 5 = ______Step 3: Multiply by the numerator:______ x ______ = ______So, 25 of 11 is about ______.Got it? Estimate the products for the following problems:1) 15 x 162) 56 of 133) 34 of 23Estimate by Rounding to 1, 0, or 12If the _________________ of a fraction is almost as big as the __________________, round up to _______.Example: 78 rounds to 1If the_________________is much _________________ than the denominator, round down _______.Example: 18 rounds to 0If the numerator is close to ____________ of the fraction, round to _________. Example 3: Estimate 13 x 79. 13 ≈ _______79 ≈ ______________ x _______ = _______So, 13 x 79 is about _______Example 4: Estimate 19 x 45.19 ≈ _______45 ≈ ______________ x _______ = _______So, 19 x 45 is about _______. Got it? Estimate: 4) 58 x 9105) 56 x 9106) 56 x 19Example 5Estimate the area of the flowerbed. Round each mixed number to the nearest whole number.1478 ft ≈_______ft618 ft ≈ _______ ft_______ x _______ = _______So the area is about _______?ft2.Got it? 7) A kitchen measures 2616 feet by 923 feet. Estimate the area of the kitchen.Guided Practice:Estimate each product. 1. 18×15= __________ 2. 25 of 26 = __________3. 15×89 = __________4. 623×415 = __________5. A border is made of 3223 bricks that are 116. About how long is the border? 6. Give an example where you would estimate two mixed numbers to equal a product of 12. Lesson 4-2 Multiply Fractions and Whole NumbersCommutative property - ________________________________________________________________________________________________________________________Example:Non-Example:Example 1Find 2 x 25Step 1: Write the whole # as a fraction2 = 21Step 2: Multiply across (numerator by numerator and denominator by denominator)21 x 25 = _________Got it? 1) 23 x 62) 13 x 93) 18 x 4Example 2Find 35 x 4Step 1: Write the whole number as a fraction4 = ________Step 2: Multiply across41 x 35 = __________Step 3: Simplify by dividing ________ = ______Example 3Find 14 x 5Step 1: Write the whole number as a fraction5 = ________Step 2: Multiply across51 = 14 = ________Step 3: Simplify by dividing________ = ________Got it? 4) 12 x 35) 25 x 46) 34 x 5Example 4A sloth spends 45 of its life asleep. If a sloth lives to be 28 years old, how many years does it spend asleep?Find 45 x 28Multiply: 45 x 281 =________Simplify: ________= ________A sloth spends ________ years of its life asleep.Got it? 7) A cat spends 23 of its life asleep. If a cat lives to be 15 years old, how many years did it spend asleep?Guided Practice: Multiply. Write in simplest form. 1. 10×45 = _________2. 2×34 = _________3. 38×11 = _________4. 49×9 = _________5. Create two fractions that when multiplied the numerator equals 8. (Before or after being simplified) Lesson 4-3 Multiply FractionsStep 1: Multiply the _________________________Step 2: ______________ the denominatorsStep 3: SimplifyExample 1:Find 13 x 14. Write in simplest form.Multiply the numerators and denominators:13 x 14 = __________Got it? 1) Find 12 x 352) Find 13 x 343)Find 23 x 56Example 2:Find 34 x 56. Simplify.Can we simplify, before we multiply? 3 & 6 have the common factor of ______. So divide both by _______.14 x 52 = _________Example 3:Find 49 x 18. 49 x 181Can we simply before we multiply? ______41 x 21 = _______ or ______Got it? 4) 34 x 495) 56 x 9106) 35?x 10Example 4Frank had 12 of the lawn left to mow. On Saturday, he mowed 23 of what was left. What fraction of the entire lawn did Frank more on Saturday?12 x 23 Divide the numerator and denominator by ______.11 x 13 = _______So, Frank mowed _______ of the lawn on Saturday.Got it? 7) Rick has 12 of a foot-long sub left from yesterday. He ate 13 of the leftover as a snack. What fraction of the entire sandwich did he eat as a snack?Guided Practice:Multiply. 1. 18×12 = _________2. 23×45= _________3. 45×10 = _________4. 34×12= _________5. 310×56= _________6. 35×56 = _________7. Katie used 12 of her beads to make a necklace. She used 25 of the remaining beads to make a bracelet. What fraction of the total beads did she use to make a bracelet? Lesson 4-4 Multiply Mixed NumbersMixed # to Improper FractionStep 1: Multiply the _________________ and the __________________________.Step 2: Add the___________________.Step 3: Write the fraction with the new numerator. The denominator stays the same.Example: 4234 x 2 = 88 + 3 = 11113Example 1:Find 13 x 134. Write in simplest form.Write the mixed number as an improper fraction.134 = _________Multiply across:13 x _______ = _________Example 2:Find 512 x 13. Write in simplest form.Write the mixed number as an improper fraction.512 = _________Multiply across:_________ x 13 = _________Simplify:_________ = _________Got it? 1) 23 x 2122) 38 x 313Example 3:Find 178 x 313. Write in simplest form.Write BOTH mixed numbers as improper fractions.178 = _________ 313 = _________Multiply (simplify first): _________ x _________= _________Simplify: _________ = _________Got it? 3) 123 x 247Example 4:The Hoover Dam contains 412 million cubic yards of concrete. The Grand Coulee Dam, in Washington state, contains 223 times as much concrete. How much concrete does it contain?Find 412 x 223.412 = _________223 = _________Multiply: _________x _________= _________or _________There are _________ million cubic yards of concrete in the Grand Coulee Dam.Got it? 4) Mr. Wilkins is laying bricks to make a rectangular patio. The area he is covering with bricks is 1512 feet by 934 feet. What is the area of the patio?What if……you multiply a fraction by a fraction? It is a fraction (less than 1)…you multiply a fraction by 1? It is that fraction (anything multiplied by 1 is just that number)…you multiply a fraction by a mixed number? It equals a mixed number (greater than 1)Guided Practice:Multiply.1. 12×238 = ________2. 134×245 = ________3. Melanie is training for a track meet. She ran 214 miles 5 times this week. How many miles did she run total? Lesson 4-6: Divide Whole Numbers by FractionsReciprocal – _______________________________________________________Example:In other words “_______________________” the fraction!Example 1:Find the reciprocal of 23Since23 x 32 =______ , the reciprocal is _______It’s okay if the final answer is an improper fraction.Example 2:Find the reciprocal of 18.Flip flop: ______ or ______ Example 3:Find the reciprocal of 5.5 x 15 = ______So the reciprocal of 5 is _______. Got it? Find the reciprocal of each number.1) 342) 133) 11 Example 4:Find 2 ÷ 13.Multiply by the reciprocal (aka Flip Flop Multiplop)21 x ______ = ________ or ______Model it:99060012065000Example 5:Got it? 4) 6 ÷135) 5 ÷ 236) 4 ÷34Example 6At summer camp, the duration of a field hockey game is 34 hour. The camp counselors have set aside 6 hours for field hockey games. How many games can by played?6 ÷ 34= 61 x ____________ x ______ = 81 or ______ gamesGot it? 7) A neighborhood development that is 4 acres is to be divided into 23-acre lots. How many lots can be created? Guided Practice:Find the reciprocal. 1.172. 4Divide. Write in simplest form. 3. 2÷134. 2÷455. A relay race is 4 miles long. If each runner in the race runs 23 mile, how many runners are in the race? Lesson 4-7: Divide FractionsExample 1:Find 12 ÷ 13. Write in simplest form.Flip flop the DIVISOR ONLY. (The second number)The reciprocal of 13 is ______.Multiply.12 x ______ =12 x _______ = _______Simplify._______ = _______Got it? 1) 14 ÷ 382) 23÷383) 56÷13Example 2:Write a story context for 23 ÷ 16.Mariska has 23 pounds of sunflower seeds. Each day she feeds the cardinals in her yard 16 pound of seeds. For how many days will she be able to feed the cardinals?Got it? 4) Write a story context for 34 ÷ 18.Outline:(Name) has (first fraction) of ___________. Each day she/he give out (second fraction) of _________. For how many days will she/he (fill in based on your scenario)? ________________________________________________________________________________________________________________________________________________________________________________________________________________________Example 3:Find 57 ÷10. 57 ÷101 =57 x__________ = _______________Got it? 5) 89 ÷ 46) 45÷87) 1213÷4Example 4Ramon is making party favors. He is dividing 34 pound of almonds into 12 packages. Write and solve an equation to find how many pounds of almonds are in each package.34 ÷12 =34 x _________ =Got it? 8) A neighborhood garden that is 23 of an acre is to be divided into 4 equal-size sections. Write and solve an equation to find the size of each section.Guided Practice:Divide. Write in simplest form. 1. 14÷12 = 2.56÷23 = 3. 18÷3= Lesson 4 - 8 Divide Mixed NumbersExample 1: Find 134 ÷ 25.Write the mixed number as an improper fraction.134 = _______Find the reciprocal of the divisor and multiply. ______ x _______ = __________Simplify. _______= 4 _______Example 2:Find 3 34 ÷ 45.Convert the mixed number to an improper fraction.3 34= _______Find the reciprocal of the divisor and multiply. _______ x _______=? _______Simplify. _______ = 4 _______Got it? 1) 2 38 ÷ 142) 212÷373) 5 58 ÷ 34Example 3:Find 512 ÷ 212.Write both mixed numbers as improper fraction.512 = _______ 212 = _______Find the reciprocal of the divisor and multiply._______ x _______= _______Simplify. _______ = _______Example 4:Find 423 ÷ 134.Write both mixed numbers as improper fractions.4 23 = _______134 = _______Find the reciprocal of the divisor and multiply._______ x _______ = _______Simplify._______= _______Got it? 4) 415 ÷ 213 5) 8÷2126) 159÷213Example 5The average adult male Giant Panda weighs about 115 times as much as the average adult female. If the average weight of a male Giant Panda is 330 pounds, how much does the average female weigh?Solve: 330 ÷ 115_______ x _______= _______or _______ poundsGot it? 7) The soccer team has 1612 boxes of wrapping paper left to sell. If each of the 12 players sells the same amount, how many boxes should each player sell?Guided Practice:Divide. Write in simplest form. 1. 312÷12 = ___________2. 223÷116 = ___________3. A box of snack-size cracker packs weighs 2812 ounces. Each snack pack weighs 434 ounces. How many snack packs are in the box? Lesson 4 - 5 Convert Measurements unit ratio – ______________________________________________________________Example: dimensional analysis – ___________________________________________________________________________________________________________________________81280010858500Example 1:Convert 20 feet to inches.Multiply or divide? __________________ x ________ = _________ inchesGot it? 1) 36 yd = _______ ft 2) 34?T=? ________ lb 3) 112 qt = ________ ptExample 2:Marco mixes 14 cup of fertilizer with soil before planting each bulb. How many fluid ounces of fertilizer does he use per bulb?Multiply or divide? __________________ x ________ = _________ ouncesGot it? 4) Jen runs 18 of a mile before tennis practice. How many feet does she run before practice?Example 3Convert 15 quarts to gallons.Multiply or divide? __________________ ÷________ = _________ gallonsGot it? 5) 2,640 ft = _______ mi 6) 100 oz = _______ lb7) 3 c = _______ ptExample 4Ava needs 4 12 feet of fabric to make a costume for a play. How many yards of fabric does she need?Multiply or divide? __________________ ÷________ = _________ yardsGuided Practice:1. 513 yards = ____________ ft 2. 412 pints = ______________ cups 3. 12 quarts = _____________ gal4. 28 in. = _________________ feet5. A large grouper can weigh 13 ton. How much does a large grouper weigh to the nearest pound? 6. The world’s narrowest electric vehicle is about 35 inches wide. How wide is this vehicle to the nearest foot? Math Vocabulary Vocabulary WordBook DefinitionDefinition in my WordsPicture or example to help me remember!Commutative Propertystates that the order in which numbers are multiplied does not change the productdenominatorthe part of the fraction that tells you how many pieces to cut the whole intodimensional analysisprocess of including units in fractions when you multiplyfractiona number that represents a part of a whole or a part of a setimproper fractiona fraction with a numerator that is greater than the denominatormixed numbera number made up of a whole number and a fractionnumeratorthe part of the fraction that tells how many units the fraction containsreciprocalany two numbers with the product of 1simplest formThe form of a fraction when the GCF of the numerator and denominator is 1unit ratioa ratio with the denominator of 1 unit ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download