Answer:the length of the shorter string= 36cm
Step-by-step explanation:
Let us assume the lengths are 2x and 7x since thery are in the ratio of 2 :7
Such that Length of the shorter string = 2x
and the longer string = 7x so that the difference in Length which is 90cm can be expressed as
7x- 2x= 90
5x= 90
x 90/5
x= 18
shorter string = 2 x = 2x 18= 36cm
Longer strring = 7x 18=126cm
The least common multiple is 96
Answer:
CI = 21 ± 0.365
Step-by-step explanation:
The confidence interval is:
CI = x ± SE * CV
where x is the sample mean, SE is the standard error, and CV is the critical value (either t score or z score).
Here, x = 21.
The standard error for a sample mean is:
SE = σ / √n
SE = 3.2 / √510
SE = 0.142
The critical value is looked up in a table or found with a calculator. But first, we must find the alpha level and the critical probability.
α = 1 - 0.99 = 0.01
p* = 1 - (α/2) = 1 - (0.01/2) = 0.995
Using a calculator or a z-score table:
P(x<z) = 0.995
z = 2.576
Therefore:
CI = 21 ± 0.142 × 2.576
CI = 21 ± 0.365
Round as needed.
Answer:
B
How many times greater in the area of the signal from transmitter
