Question

Half of your baseball card collection got wet and was ruined. You bought 20 cards to replace some that were lost. how many did you begin with if you now have 50?

Answer 1

60

Explanation:

Given the following :

Half of baseball card got wet and was ruined

Number of baseball cards bought has replacement for the ruined cards = 20

Total number of baseball cards now = 50

The initial number of baseball cards =?

Let the initial number = y

Number that hit ruined = half of initial = y/2

Hence,

y - y/2 + 20 = 50

y/2 + 20 = 50

y/2 = 50 - 20

y/ 2 = 30

y = 30 * 2

y = 60

Hence, he started with 60 baseball cards.