Statisticsmedium · Past Paper
A student scored 60, 70, and 80 in three tests. What score does he need in the fourth test to have a mean of 75?
A85
B90
C80
D95
✓ Correct Answer: B — 90
Total sum needed = 75 * 4 = 300. Current sum = 60+70+80 = 210. Required = 300 - 210 = 90.
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