Question

If x & y are in direct proportion then find the value of a

x	2	3	5	7
y	4	6	a	14

• A. $8$
• B. $10$
• C. $15$
• D. $20$

Answer 1

The correct option is B $10$

We know that, in direct proportion, the ratio of the quantities remains constant

$\therefore \frac{x}{y}=k$

$\frac{2}{4}=\frac{3}{6}=\frac{5}{a}=\frac{7}{14}=k\Rightarrow k=\frac{1}{2}=\frac{5}{a}\Rightarrow a=10$

Thus option B is the correct answer.