Answer:
A) 68.33%
B) (234, 298)
Step-by-step explanation:
We have that the mean is 266 days (m) and the standard deviation is 16 days (sd), so we are asked:
A. P (250 x < 282)
P ((x1 - m) / sd < x < (x2 - m) / sd)
P ((250 - 266) / 16 < x < (282 - 266) / 16)
P (- 1 < z < 1)
P (z < 1) - P (-1 < z)
If we look in the normal distribution table we have to:
P (-1 < z) = 0.1587
P (z < 1) = 0.8413
replacing
0.8413 - 0.1587 = 0.6833
The percentage of pregnancies last between 250 and 282 days is 68.33%
B. We apply the experimental formula of 68-95-99.7
For middle 95% it is:
(m - 2 * sd, m + 2 * sd)
Thus,
m - 2 * sd <x <m + 2 * sd
we replace
266 - 2 * 16 <x <266 + 2 * 16
234 <x <298
That is, the interval would be (234, 298)
If you think about what times what equals 93.
Type in the calculator square root of 93, and you get 9.643650761... but you want to round this decimal to the nearest tenth or hundredth... so 9.64
Hi there
The future value formula is
Fv=pmt [(1+r)^(n)-1)÷r]
Solve the formula for PMT
PMT=Fv÷[(1+r)^(n)-1)÷r]
So
PMT=5,330÷(((1+0.08)^(24)−1)÷(0.08))
PMT=79.83
Good luck!