Question

1. If the cost of 10 pens cost is Rs. 80. Find the cost of 15 pens​

Answer 1

Answer:

Rs. 120

Step-by-step explanation:

If the number of pens increases, the cost also increases. So, we will use direct proportionality, here.

10 pens = Rs. 80

1 pen = Rs. 80/10 = Rs. 8

15 pens = Rs. 8 × 15 = Rs. 120

Answer 2

Answer:

Cost of 10 pens = Rs 80

.•. Cost of one pens = 80 ÷ 10 = Rs8

.•. Cost of 15 pens = Cost if one pens × number of pen

= 15 × 8

= Rs 120 /-

.•. Cost of 15 pens is Rs 120/-