What is one third of 2 and five eighths

Question

If I use one third of perfume that has 2 and five eighths ounces then how much perfume do I have left

Answer 1

if you have used 1/3 of it, it means 2/3 left.

so you need to find 2/3 of 2 5/8

2 and 5/8 is 21/8

21/8 multiply by 2/3

(21 x 2)/(8 x 3)=42/24=21/12=7/4= 1  3/4