Answer:
5.61×10^8 ton/day
Step-by-step explanation:
(2.08×10^5 ft³/s)·(8.64×10^4 s/day)·(6.24×10^1 lb/ft³)/(2×10^3 lb/ton)
= (2.08·8.64·6.24/2)×10^(5+4+1-3) ton/day
≈ 56.07×10^7 ton/day
≈ 5.61×10^8 ton/day
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We have expressed the answer using 3 significant digits, to match the precision of the rate and weight.
The temperature at 6am would've been -2 because 3 - 5 = -2
We need to represent the numbers of calls symbolically:
Third evening: x calls
First eve: x-6 calls
Second evening: 3x calls
Find x. Add up these three numbers x, x-6 and 3x and equate your sum to 79:
x+x-6+3x = 79. Then 5x=79+6, or 5x = 85. Thus, x = 17.
17 calls on the 3rd night,
17-6 calls on the 1st night, and
3(17) = 51 calls on the 2nd night.
Check! Add together 17, 11 and 51. Do these add up to 79? Yes.