Answer:
C. 2.0 < t < 2.5
Step-by-step explanation:
time = distance / speed
The circumference of the lake is given by ...
C = πd = 2π miles ≈ 6.28 miles
Then Johanna's time is ...
(6.28 mi)/(3 mi/h) ≈ 2.09 h
This time is in the interval (2, 2.5), so matches choice C.
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<em>Alternate solution</em>
If we take pi to be 3, then this boils down to ...
2×3/3 = 2 . . . hours
Pi is on the order of 5% more than 3, so her time will be on the order of 5% more than 2 hours, or just above 2, but not as great as 2.5 hours. This sort of estimating can get you to the correct answer without a calculator.
Answer:
There are 15 letters, but if the two A's must always be together, that's the same as if they're just one letter, so our "base count" is 14! ; note that this way of counting means that we also don't need to worry about compensating for "double counting" identical permutations due to transposition of those A's, because we don't "count" both transpositions. However, that counting does "double count" equivalent permutations due to having two O's, two N's, and two T's, so we do need to compensate for that. Therefore the final answer is 14!/(23)=10,897,286,400
The answer would be SSS or Side-Side-Side.
6 girls would need to join for the ratio to be the same
