Question

Make up as many expressions with numbers (no variables) as you can from three numbers 5, 7 and 8. Every number should be used not more than once. Use only addition, subtraction and multiplication.

(Hint: Three possible expressions are 5 + (8 − 7), 5 − (8 − 7), (5 × 8) + 7; make the other expressions.)

Answer 1

Many expressions can be formed by using the three numbers 5, 7, and 8.

Some of these are as follows.

1. 5 × (8 − 7)
2. 5 × (8 + 7)
3. (8 + 5) × 7
4. (8 − 5) × 7
5. (7 + 5) × 8
6. (7 − 5) × 8