Question 57
HardOriginal questionEvaluate .
Show the answer and explanation
CorrectNot quiteAnswer D
Correct answer: D
Explanation
, so .
, so .
, so .
Value .
Worth noting
Decimal powers become easy once each base is a clean power: 0.8 of five 3s is four 3s. Taking as a square root (9) gives 72.
- Concept
- Decimal indices by rewriting bases as powers
- Typical timeTypical
- 90 s
- Your timeYours
- —
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