Advanced Math practice question

Answer: 20

When t increases by 3, the exponent increases by 1, so P is multiplied by 0.8: a 20% decrease.

Common wrong answers

If you answered 80

80% is what remains, not the decrease.

If you answered 6.67

6.67% would be the naive per-hour figure, 20/3, which is not what the question asks.

If you answered 0.8

0.8 is the multiplier, not a percent decrease.

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