To find the contribution of each man (this is a sexist problem as women could work as well, but that’s besides the point) take 5/2 and then multiply that value by 20 and you’ll find it takes 50 hours for two men to do it.
Answer: 50 hours
A) 0.2076
B) 0.6786
C) 0.3214
Explanation:A)
B) We find the probability that X=6, 7, or 8:
C) P(X≤5) = 1-P(X>5) = 1-0.6786 = 0.3214
2 is not divisible
3 is not divisible
4 is not divisible
5 is not divisible
6 is not divisible
9 is not divisible
And 10 is not divisible
(A) is an irrational sum
(C) is also an irrational sum
(D) is an irrational sum too
Answer: Any number larger than 14.3; one possible value is 20
Note how 20 + (-14.3) = 20-14.3 = 5.7 which is positive.
If we picked something smaller than 14.3, like say 10, then
10+(-14.3) = 10-14.3 = -4.3 which is negative.
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When adding a positive to a negative, you basically subtract the two values. Then whatever the largest value is, that's the sign of your result. For 20+(-14.3), the positive 20 is larger in absolute value so the overall result is positive. On the other hand, the -14.3 is larger in magnitude compared to the 10, which is why 10+(-14.3) has a negative result.
