Question

Linda's penny bank is 2/3 full. After she removes 80 pennies, it is 1/2 full. How many pennies can Linda's bank hold?

Answer 1

Let x = the total number of pennies her piggy bank can hold.
Then 2/3x = the number of pennies she started with
Then 2/3x - 80 = the number of pennies she has left after taking out 80 pennies.
Then 1/2x = the number of pennies she has left after taking out 80 pennies.
Build the equation.

2/3x - 80 = 1/2x

Subtract 1/2x from each side of the equation.

(2/3x - 80) - 1/2x = 1/2x - 1/2x

1/6x - 80 = 0

Add 80 to both sides of the equation.

(1/6x - 80) + 80 = 0 + 80

1/6x = 80

Divide both sides by 1/6.

(1/6x) / 1/6 = 80 / 1/6

x = 480

So, Linda's piggy bank can hold 480 pennies!