How many questions do you need to get right for at least a score of 100 when answering 126 out of 126 gets a score of 176 answering 0 gets you 0 and answering 63 gets 88?

Answer 1

Assuming every question has the same score, then:

if 126 questions correct score 176, each question scores 176/126 points

With 0 correct this gives a score of 0 × 176/126 points

With 63 correct this gives a score of 63 × 176/126 = 88 (as given).

To score at least 100:

number of questions × 176/126 ≥ 100

→ number of questions ≥ 100 × 126/176 = 71 13/22

Assuming you cannot answer part of a question to get the mark, you must answer at least 72 questions to get a score of 72 × 176/126 = 100 4/7

If you were to get only 71 questions right you would score 71 × 176/126 = 99 11/63 which is less than 100.

You need to get 72 questions right to get a score of at least 100.