The average temperature from Monday to Wednesday was 37 °C and from Tuesday to Thursday was 34 °C. If Thursday's temperature was 4/5 of Monday's, what was Thursday's temperature?
Correct answer: C. 36 °C
Monday − Thursday = 3 × 37 − 3 × 34 = 9. With Thursday = 0.8 × Monday, 0.2 × Monday = 9, so Monday = 45 °C and Thursday = 36 °C.
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