He needs to work 22 hours :)
Answer: 1/7
Step-by-step explanation:
Total questions answered = 49
Harry correct answers = 42
Harry wrong answers = (49 - 42) = 7
Thus, the only fraction of wrong answers = (Number of wrong answers / Total number of questions answered)
i.e 7/49
= 1/7
Thus, harry answered 1/7 of the 49 questions wrongly.
The answer to the question is $4.7
You can prove the proofs by showing your work to prove the proofs.