Question

If $\frac{a}{10}$ = $\frac{b}{4}$ = $\frac{c}{6}$ = $\frac{4a-3b+9c}{x}$. The value of x is .

• A. 41
• B. 82
• C. 84
• D. 42

Answer 1

The correct option is B 82

$\frac{a}{10}$ = $\frac{b}{4}$ = $\frac{c}{6}$ = $\frac{4a-3b+9c}{x}$.

Multiply numerator and denominator of $\frac{a}{10}$ by 4 = $\frac{4a}{40}$ ....1

Multiply numerator and denominator of $\frac{b}{4}$ by -3 = $\frac{-3b}{-12}$ ....2

Multiply numerator and denominator of $\frac{c}{6}$ by 9 = $\frac{9c}{54}$ ....3

As per the theorem of equivalent ratio and using 1, 2 and 3,

$⟹$ $\frac{4a-3b+9c}{40-12+54}$= $\frac{4a-3b+9c}{x}$.

Hence, x = 82.