Statisticsmedium · Past Paper
A student scored 70, 80, and 90 in three tests. What score does he need in the fourth test to have a mean of 85?
A90
B100
C95
D85
✓ Correct Answer: B — 100
Total sum needed = 85 * 4 = 340. Current sum = 70+80+90 = 240. Required = 340 - 240 = 100.
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