If 20% of a number is subtracted from a second number and the second number decreases to its 70%, then what is the ratio of the first number to the second number?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 3:2.
Let;
First number = x
Second number = y
According to the question:
⇒ y − 20% of x = 70% of y
⇒ y − 20/100 x = 70/100 y
⇒ 100y − 20x = 70y
⇒ 30y = 20x
⇒ 3y = 2x
⇒ y/x = 2/3