Answer:
A. 4·10⁴
Step-by-step explanation:
The problem statement tells you ...
6×10⁵ miles = 15 × (last year's mileage)
Dividing by 15 gives ...
(60×10⁴ miles)/15 = (last year's mileage) = 4×10⁴ miles
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<em>Further explanation</em>
An exponent is an indication of repeated multiplication.
10⁵ = 10·10·10·10·10 = 100,000
We can use the associative property of multiplication to rewrite the number of miles:
6×10⁵ = 6·(10·10·10·10·10) = 600,000 = (6·10)·(10·10·10·10) = 60×10⁴
I would personally take the number three and trow it out the window but that's not what we are talking about
Answer:
2.5 miles
Step-by-step explanation:
The relation between time, speed, and distance is ...
distance = speed × time
We can define t to be Stanley's swimming time. Then t+0.5 was his running time, and 2(t+0.5) was his biking time. His total distance covered is ...
64 = 9(t +0.5) +16(2(t +0.5)) +2.5(t)
64 = 43.5t +20.5 . . . . . . . simplify
43.5 = 43.5t . . . . . . . . . subtract 20.5
t = 1 . . . . . . . . . . . . . . divide by the coefficient of t
Stanley swam for 1 hour, so the distance he covered while swimming was ...
(2.5 mi/h)(1 h) = 2.5 mi
Stanley covered 2.5 miles while swimming.
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<em>Additional comment</em>
Stanley ran for 1.5 hours, covering 9×1.5 = 13.5 miles. He biked for 3 hours, covering 16×3 = 48 miles. His total distance was 2.5 +13.5 +48 = 64 miles, as given.
I'd say the answer is 5 wins
hope this helps
