Question

Derrick got a pizza for lunch. He gave his friend 1/4 of the pizza and his sister 3/8 of the pizza. How many pizza he will have left

Answer 1

ANSWER: 3/8

let's assume that Derrick is a nice guy and his pizza is an integer of 1

first he gave his friend a quarter so we subtract
`(1)/(4)` from 1

`1-(1)/(4)`

now we rewrite 1 as a fraction with a denominator of 4 so that we're able to subtract:
`(4)/(4)-(1)/(4) =(3)/(4)`

now that Derrick still has
`(3)/(4)` of his pizza he's gonna give
`(3)/(8)` to his sister as well

meaning that we subtract again:
`(3)/(4) -(3)/(8)`

in order to be able to subtract different fractions, they got to have the same denominator, so we're going to multiply
`(3)/(4)` both numerator and denominator by 2:
`(2*3)/(2*4) -(3)/(8) = (6)/(8) -(3)/(8) = (3)/(8)`

we can now conclude that Derrick is left with only
`(3)/(8)` of his pizza.

Answer 2

Answer: 3/8

Step-by-step explanation: 1/4 x 2 = 2/8 + 3/8 = 5/8 pizza gone. 1 - 5/8 = 3/8