Question

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

Answer 1

Solution :

using 5,8,7 we need to make expressions

Expressions can be

$5+(8+7)$ $5-(8+7)$ $5\times (8-7)$

$5+(8-7)$ $5-(8-7)$ $5\times (7-8)$

$5+(7-8)$ $5-(7-8)$ $5\times (8\times 7)$

$5+(8\times 7)$ $5-(8\times 7)$ $5\times (8+7)$

$8+(5-7)$ $8-(5+7)$ $8\times (5+7)$

$8+(7-5)$ $8-(5-7)$ $8\times (5-7)$

$8+(5\times 7)$ $8-(7-5)$ $8\times (7-5)$

$8-(5\times 7)$

$7+(8-5)$ $7-(5+8)$ $7\times (5+8)$

$7+(5-8)$ $7-(8-5)$ $7\times (8-5)$

$7+(5\times 8)$ $7-(5-8)$ $7\times (5-8)$

$7-(5\times 8)$