Question

Zen bought some chocolates for his friends. If he gives 6 chocolates to each friend,
he would have 4 chocolates remaining. If he gives 7 chocolates to each friend,
he would be short of 2 chocolates. Find the number of chocolates Zen bought.

Answer 1

Step-by-step explanation:

$let \: the \: chocolates \: be \: x \: and \\ frind \: number \: y \: \\ first \: condition. \\ x - 6y = 4 \\ second \: condition \\ x - 7y = - 2 \\ let \: subtract \: them \\ x - 6y = 4 \\ x - 7y = - 2 \\ - \: \: \: \: + \: \: \: \: \: \: \: + \: \\ - - - - - - - \\ y = 6 \\ - - - - - - - - - - - \\ in \: the \: first \: equation \: we \: \\ put \: the \: value \: of \: y \: \\ x - 6 \times 6 = 4 \\ x - 36 = 4 \\ x = 4 + 36 \\ x = 40 \\ zen \: bought \: 40 \: chocolates$

the symbols will change during subtraction.

Hope it will help