MODELS AND SUPER-MODELS: WAYS OF THINKING ... - …

Same as 90% of £73, so 9£7.30 = £65.70 NT2 Mentally: 10% makes the tens into units so £4. 30% is 3 times bigger making £12. Half of £4 is £2, so the total is £14 Mentally: £8 - I just know it - plus £80 is £88 Mentally: 10% is £7.30. Written: 7.30 9 = … ................
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