Henry purchased x apples and Jack purchased 10 apples fewer than one-third of the number of apples Henry purchased. Are these amounts equal?

A-the number of apples Jack purchased
B-x-30 divided by 3

2 answers

(x/3)-10 = Jack = (x-30)/3

yes, the right and the left are equal, but you can not solve for x without knowing more.
for example if you know jack bought 20 apples
then
20 = (x-30)/3
60 = x-30
x = 90 for Henry

check
90/3 - 10 = 20 for Jack