Katie made some chocolate truffles. Katie gave 1⁄4 of her truffles to Leanne. Then Katie gave 1⁄2 of the remaining truffles to Jeff. At that point, Katie had 18 truffles left. How many chocolate truffles did Katie have at first?

Answer 1

Never heard of a subject called Tupper.

anyhow....

let the number of Katies truffles be x

after first gifting:
Katie had (3/4)x left
she gave 1/2 of those away leaving her with
(1/2)(3/4)x or (3/8)x truffles

(3/8)x = 18
3x = 144
x = 48

So she started with 48

check:
she gave 1/4 away or 12, so she is left with 36
she then gave half of those away, leaving her with 18
all checks out.

Answer 2

"Tupper" is a school subject I have not heard of.