Last year He was 7 years old.
His father is 4 times the age 7 x 4 = 28
Last year his dad was 28, so this year he is 29.
Combined age this year = 29 + 8 = 37
51 - 37 = 14 years
14/ 2 people = 7 years
8 + 7 = 15
29 + 7 = 36
15 + 36 = 51
It will take 7 years.
Answer:


And the margin of error with this one:


Step-by-step explanation:
Assuming that the parameter of interest is the sample mean
. And we can estimate this parameter with a confidence interval given by this formula:
(1)
For this case the confidence interval is given by (1.9, 3.3)
Since the confidence interval is symmetrical we can estimate the sample mean with this formula:


And the margin of error with this one:


Let the number of rows be x
rows = x
seats in each row = x + 20
total seats = 1344
x (x + 20) = 1344
x^2 + 20x - 1344 = 0
(x + 48)(x - 28) = 0
x = -48 (rejected, answer cannot be negative) or x = 28
Therefore,
x = 28
x + 20 = 48
Check:
Row = 28
Numbers of seat per row = 28 + 20 = 48
28 x 48 = 1344 (Correct)
Ans:There are 48 seats per row
The anwser is (B) hope this helped