Question

Govind has enough money to buy 16 pens at the rate of Rs 15 per pen. If the cost of a pen is increased by Rs 9, how many pens can Govind buy?

Is this Inverse Or Direct Variation,
How do you do it then?

Answer 1

cost- 15-24
no. of pens-16-y

by inverse variation (because when rate increases no. of pens decreases.)

15*16=24y
15*16/24=y
y=10

he can buy 10 pens at the increased price