Answer:
P(X > 10), n = 15, p = 0.7
P(X > 10) =P(10 < X ≤ 15) = P(11 ≤ X ≤ 15) = P(X = 11, 12, 13, 14, 15)
=P(X = 11) + P(X =12) + P(X = 13) + P(X =14) + P(X = 15) (because these are disjoint events)
Step-by-step explanation:
See attached image for detailed explanation
Answer:
4.98
Step-by-step explanation:
A mountaineer climbed 1000 feet at a rate of x feet/hour
1000 = x ( t 1 ) eq1
5000 = X ( t 2) eq2 ( he climbed additional at different rate )
the rate was 10 feet / hour less than twice the first rate
X = 2x - 10 eq3
take eq1 and eq 2
( total time = t 1 + t 2 = T)
T = 1000/x + 5000/X
but X = 2x-10
T = 1000/x + 5000/( 2x -10)
T = 1000/x + 5000/( 2(x-5))
T = 1000/x + 2500 / (x-5)