Can someone please help me with this Pre-algebra problem?

Question

I’m trying to help my younger brother with his homework, but I’m not sure if he’s correct. Can someone please help?

Valerie used 2/3 of a full spool of string for her project. There were 47 inches of string left on the spool when she was done. How many inches of string were on the full spool?

(A) 138

(B) 31 1/3

(C) 70 1/2

(D) 141

He got (D) for this problem.

Answer 1

47 = 1/3 of the spool

the spool = (3)47= 141

d) is correct

Answer 2

Answer D is correct

Let T = total length on spool

Used 2/3 of T

Left = T -2/3 T =( 1/3)T =47

T = 47*3 = 141 inches