Quantitative Aptitude Ques 4

Question: The LCM of two numbers is 4 times their HCF. The sum of LCM and HCF is 125. If one of the numbers is 100, then the other number is

Options:

A) 5

B) 25

C) 100

D) 125

Show Answer

Answer:

Correct Answer: B

Solution:

  • Let LCM be x and HCF be y. According to the question, $ LCM=4\times HCF $
    $ \Rightarrow $ $ x=4y $ and $ LCM+HCF=125 $ $ x+y=125 $ On putting the value of x, we get $ 5y=125 $
    $ \Rightarrow $ $ y=25 $

$ \therefore $ $ HCF=25 $ and $ LCM=4\times 25=100 $ We know that, HCF $ \times $ LCM = First number $ \times $ Second number

$ \therefore $ Second number $ =\frac{HCF\times LCM}{First,number}=\frac{100\times 25}{100}=25 $