Step-by-step explanation:
25 questions, 2 points each.
that means there were 25×2 = 50 points in total.
Gideon got 42 out of the 50.
100% = 50
1% = 100%/100 = 50/100 = 0.5
42 is how many % ? as many as 1% (0.5) fits into 42.
so,
42/0.5 = 42×2 = 84%
he scored 84%.
