Question

Find X, $\frac{1}{5}:\frac{3}{4}:\frac{2}{7}:X?$

• A. 4/7
• B. 15/14
• C. 6/5
• D. 12/15

Answer 1

Answer:

B. 15/14

Solution:

Given:

$\frac{1}{5}:\frac{3}{4}:\frac{2}{7}:X$

Concept used:

When a, b, c and d are in proportion then,

a : b :: c : d

⇒ ad = bc

Calculation:

$\frac{1}{5}:\frac{3}{4}:\frac{2}{7}:X$

here $a=\frac{1}{5}, b=\frac{3}{4},c=\frac{2}{7},d=x$

$ad=bc$

$\frac{1}{5}\times{x}=\frac{3}{4}\times{\frac{2}{7}}$

$\frac{x}{5}=\frac{3}{14}$

$x=\frac{15}{14}$