Question

A student has passed 60 percent of the 20 quizzes he has written so far successfully. If the student writes 50 quizzes during the year, and passes 80 percent of the remaining quizzes successfully, what is the percent of all successful quizzes for the entire year?
Plz help thanks!

Answer 1

60% of 20 quizzes = 60/100*20 quizzes = 12 quizzes

Amount of quizzes remaining = 50 quizzes - 20 quizzes = 30 quizzes

He passes 80% of those 30 quizzes, so

80/100 * 30 quizzes = 24 quizzes

So, he passed 12 quizzes from the initial bunch and 24 quizzes from the rest, which totals to 12 quizzes + 24 quizzes = 36 quizzes.

Then, you see that he passed 36 quizzes, out of the total 50 quizzes, so the ratio is 36 quizzes / 50 quizzes = 36/50, which when converted as a percentage is 36/50 * 100% = 72%.

Therefore, he passed 72% of the quizzes for the entire year.