How to see it
An improper fraction has a top bigger than its bottom. A mixed number has whole ones and a fraction. To change mixed to improper: how many fifths in the wholes? Three wholes are fifteen fifths. Then add the two. Seventeen fifths.
A worked example
Now backwards. 23 over 6. How many sixes fit into 23? Three, with 18 used. Five left over. Three and five sixths.
The common mistake: gluing the whole number to the numerator
The trap is gluing: 3 and 2 over 5 becomes 32 over 5. The whole number has to be turned into fifths first. Three times five, plus two.
Try one
Write 4 and 3 eighths as an improper fraction.
- A43/8
- B12/8
- C35/8
- D11/8
Show the answerHide the answer
Right: C, 35/8
4 × 8 is 32, plus 3.