Question

Let the numbers $a,b,c,d$ are in continued proportion in order. If the value of $b$ and $c$ are $6$ and $18$ respectively, then

• A. $a=2$
• B. $a=3$
• C. $d=36$
• D. $d=54$

Answer 1

Answer: (A), (D)

The correct options are
A $a=2$
D $d=54$

If $a,b,c,d$ are in continued proportion, then
$\frac{a}{b}=\frac{b}{c}=\frac{c}{d}\Rightarrow \frac{a}{6}=\frac{6}{18}=\frac{18}{d}\Rightarrow \frac{a}{6}=\frac{1}{3}=\frac{18}{d}\therefore a=2,d=54$