Banking Quantitative Aptitude Sample Paper Quantitative Aptitude Sample Paper-34

LCM of two numbers is 28 times their HCF. The sum of HCF and LCM is 1740. If one of these numbers is 240, the sum of digits of the other number, is                                                         [NICL (AO) 2012]

A) 4

B) 5

C) 6

D) 7

E) None of these

Correct Answer: C

Solution :

Let LCM of the two numbers\[=x\]

Then, HCF of the two numbers \[=\frac{x}{28}\]

Now, \[x+\frac{x}{28}=1740\]\[\Rightarrow \]\[\frac{29x}{28}=1740\]

\[\Rightarrow \]\[x=\frac{1740\times 28}{29}=1680\]

So, LCM of these two numbers \[=1680\]

Again, \[240\times y=1680\times 60\]

[\[\because \]first number x second number \[=\text{LCM}\times \text{HCF}\]]

\[\Rightarrow \] \[y=\frac{1680\times 60}{240}=7\times 60\]\[\Rightarrow \]\[y=420\]

Hence, other number is 420.

\[\therefore \]Sum of digits \[=4+2+0=6\]