Cos 57 it has to add up to 90
Answer:
(13.5, 34.5)
Step-by-step explanation:
The empirical rule states that for a normal distribution, the data will fall within three standard deviations of the mean. 68% of the data falls within the first standard deviation (µ ± σ), 95% within the first two standard deviations (µ ± 2σ), and 99.7% within the first three standard deviations (µ ± 3σ).
Given that mean (µ) = 24 and standard deviation (σ) = 3.5
Using empirical rule, the interval that represents the middle 99.7% = (µ ± 3σ) = (24 ± 3*3.5) = (13.5, 34.5)
W represents the weight of each book
2w + 4 = 18
2w = 18 - 4
2w = 14
w = 14/2
w = 7 oz <===
