Question

Fifteen postcards cost Rs $2.25$. What will be the cost of $36$ postcards? How many postcards can we buy in Rs $45$?

Answer 1

Given cost of 15 post cards = Rs $2.25$
Cost of 1 post card is $=\frac{2.25}{15}$
Hence, the cost of 36 post cards $=\frac{2.25}{15}\times 36=$ Rs $5.40$
Number of post cards bought for Rs $2.25=15$
Numbers of post cards bought for Rs $1=\frac{15}{2.25}$
Hence number of post cards bought for Rs $45=\frac{15}{2.25}\times 45$
$=300$