There are some cookies in the jar. On Monday, Alex ate 1/4 of the cookies. He later bought 24 cookies and added into the jar. On Tuesday, Alex ate 36 cookies. He was hungry and ate another 30 cookies. There were no cookies left. How many cookies were there in the jar at first?
x = original amount
eats 1/4 leaves 3/4 x
3/4 x + 24 - 36 - 30 = 0 solve for 'x' the original amount
Let x be the total cookies at first.
3/4x + 24 - 36 - 30 = 0
3/4x = 42
x = 56
Alex had 56 cookies in the jar at first