Question

The GCD and LCM of two numbers a and b are, respectively, 27 and 2079. If a is divided by 9, the quotient is 21. Then b is

• A. $243$
• B. $189$
• C. $113$
• D. $297$

Answer 1

The correct option is D $297$

Let the two numbers be $a$ and $b$.
$a=quotient\times dividend$
$a=21\times 9$
$=189$
$\therefore b=\frac{GCD\times LCM}{a}$
$=\frac{27\times 2079}{189}$
$=297$