Question

Write a pair of decimal whose sum is 0.9 and difference is 0.666 ..find tha pair of decimal

Answer 1

$x + y = 0.9 .........(1)\\ \\ x - y = 0.66 .........(2)\\ adding \: equation \: (1) \: and \: (2) \\ \\ 2x = 1.56 \\ \\ x = \frac{1.56}{2} \\ \\ x = 0.78 \\ \\ putting \: this \: value \: of \: x \: in \: equation \: (1) \\ \\ 0.78 + y = 0.9 \\ \\ y = 0.9 - 0.78 \\ \\ y = 0.12 \\ \\ hence \: the \: required \: pair \: of \: decimal \: is \: 0.78 \: and \: 0.12$