Question

afla nr.necunoscut:m×7+11=60;100-(7×n-3× n)=60

Answer 1

$m \times 7 + 11 = 60$

$7m = 60 - 11$

$7m = 49 \: | \div 7$

$m = 7$

$100 - (7 \times n - 3 \times n) = 60$

$100 - (7n - 3n) = 60$

$100 - 4n = 60$

$- 4n = 60 - 100$

$- 4n = - 40 \: | \div ( - 4)$

$n = 10$