MathGrit
ProblemsTechniquesPricing
Sign inGet started
Back to problems

Average Percentage Fifth Test

925BeginnerAlgebra

South African Mathematics Olympiad First Round

All my Maths tests are out of the same total, and the average of my marks in the four tests so far is $75\%$. What percentage do I need in a fifth test so that my overall average will be $80\%$? (A) $100$ (B) $90$ (C) $85$ (D) $80$ (E) $75$
0 students attempted0% solvedRating 925

Related practice paths

Olympiad-Style PracticeDeep contest practice for proof-style problem solving.How to Qualify for AIMEScore goals, contest choice, and prep habits for AIME hopefuls.How to Review Missed AMC ProblemsTurn missed problems into a repeatable improvement loop.

Ready to check your answer?

Create an account to submit answers, save history, and track your rating.

Progressive Hints

Unlock hints one at a time — each reveals a little more without spoiling the solution.

Step-by-Step Solutions1

Multiple solution approaches with detailed walkthroughs, unlocked after you solve the problem.

AI-Powered Grading

Instant feedback on your answer — handles fractions, decimals, and equivalent forms.

Curated problem bank

Supported tracks for AMC, AIME, MATHCOUNTS, and olympiad-style training, plus global problem sources like UKMT, Euclid, and Kangaroo.