Question

The price of 7 pens is Rs. 42; find the price of 13 such pens.

• A. $Rs.65$
• B. $Rs.78$
• C. $Rs.91$
• D. $Rs.26$

Answer 1

The correct option is B

$Rs.78$

Given, the price of 7 pens is Rs. 42
Using the unitary method in which we find the value of a single unit, i.e. 1, (by dividing) and then find the necessary value by multiplying the single unit value.

Price of 1 pen = $\frac{Rs.42}{7}$
$\therefore$ Cost of 13 pens $=\frac{Rs.42}{7}\times 13=Rs.78$