Answer:
Harry's solution is incorrect.
Harry can first substitute (30) for t. He can the multiply 1/3 by (30) to get a product of (10). Since 15 (≠) equal to (10), Harry's solution is (not) correct.
Step-by-step explanation:
Given:
Equation =
Solution of the equation = 
Lets check the equation whether both sides of the equation gives same result by plugging the values of t = 30.
⇒
⇒ 
⇒ 
⇒
We know that 10 ≠ 15 so the solution is incorrect.
According to the question :
Harry can first substitute (30) for t. He can the multiply 1/3 by (30) to get a product of (10). Since 15 (≠) equal to (10), Harry's solution is (not) correct.
Harry's solution is incorrect.