A is the answer i think
if not then c
Let n be the amount of time it takes william to cut the lawn. Then Shelly takes
n-2 hours. So:
1/n+1/n-2=1/3
3(n-2)+3n=n²-2n
6n-6=n²-2n
n²-8n+6=0
Using the quadratic formula, we get a positive value of 7.1623 hrs as the amount of time william takes working alone, and 5.1623 as the amount of time Shelly takes working alone
☺☺☺☺
Answer:
7÷(x+1)
Step-by-step explanation:
7÷(x+1)
Answer:
4.5 I think
Step-by-step explanation:
Step-by-step answer:
standard deviation (sigma) = 12 inches
mean (mu) = 90 inches.
For 36 years, the standard error of the mean is
e = sigma / sqrt(n) = 12" / sqrt(36) = 2".
Deviation from the mean
= 92.8 -90 = 2.8
Since the standard error of the mean follows the normal distribution, we have
Z=(92.8-90)/2 = 1.4
Looking up the normal distribution tables, or check R, we find
P(Z>1.4) = 1-P(Z<1.4) = 1-0.9192433 = 0.08075666
Answer: P(snowfall>92.8) = 0.0808 (to four decimal places)
