Question 7

Cost of 4 dozens bananas is Rs 60. How many bananas can be purchased for Rs 12.50?

Cost of 4 dozen bananas = Rs 60

Cost of 48 bananas = Rs 60 [$\because$ 1 dozen = 12 units, 4 dozen = 4 $\times$ 12 = 48]

Applying unitary method, where firstly we find the value of one unit and then the value of required number of units.

$\therefore$ From Rs 60, number of bananas that can be purchased = 48

$\therefore$ From Rs 1, number of bananas that can be purchased = $\frac{48}{60}=\frac{4}{5}$

$\therefore$ From Rs 12.50, number of bananas that can be purchased = $\frac{4}{5}\times 12.50$

$=\frac{4}{5}\times \frac{1250}{100}=\frac{250}{25}$ [multiplying numerator and denominator by 100]

= 10 bananas

Thus, 10 bananas can be purchased for Rs 12.50.