A certain weight (in kg) is divided into two parts such that 5 times the first part added to 11 times the second part makes 7 times the whole weight. The ratio of the first part to the second part is :
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 2 : 1
Write the condition as an equation. Let the two parts be \(x\) and \(y\), so the whole weight is \(x+y\):
5 times the first part added to 11 times the second makes 7 times the whole: \(5x+11y=7(x+y)\)
\(5x+11y=7x+7y\)
\(4y=2x\)
\(\displaystyle\frac{x}{y}=\frac{4}{2}=\frac{2}{1}\), so the ratio is 2 : 1