Work out 3 and 1/2 divided by 2 and 4/5

Start by converting these mixed numbers into top-heavy fractions: 3 and 1/2 becomes 7/2 (3x2=6; 6+1=7)2 and 4/5 becomes 14/5 (2x5=10; 10+4=14)Then use the 'KFC' formula - 'Keep it, flip it, calculate it': So we keep the first fraction as it is - 7/2 stays as 7/2. We then 'flip' both the sign and the second fraction - divided by becomes multiply by, and 14/5 becomes 5/14So our new equation is: 7/2 x 5/14 = ? This is much easier to work out in this form than in the form the question gives.So, as with a normal fraction multiplication, we multiply the top numbers together, and multiply the bottom numbers: 7x5=35; 2x14=28. So our answer is: 35/28But we can simplify this - both 35 and 28 divide by 7:35/7 = 528/7 = 4. So our simplified answer is: 5/4. Because the question gives the fractions as mixed numbers, we should give our answer as a mixed number too. So we write 5/4 as 1 and 1/4.

Answered by Sarah M. Maths tutor

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