Sherry first took the multiplication instead of taking the sum of 16 and 9 first.
The right expression is: 2* (16+9)
Step-by-step explanation:
Sherry's expression was:
(2*16)+9
Her expression was wrong because it is mentioned that twice the sum of 16 and 9 which means that first the sum has to be calculated then the sum will be multiplied by two.
