The 7 In 157 would round it up to 160. I hope this helps!
Answer: Choice D
(a-e)/f
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Explanation:
Points D and B are at locations (e,f) and (a,0) respectively.
Find the slope of line DB to get
m = (y2-y1)/(x2-x1)
m = (0-f)/(a-e)
m = -f/(a-e)
This is the slope of line DB. We want the perpendicular slope to this line. So we'll flip the fraction to get -(a-e)/f and then flip the sign from negative to positive. That leads to the final answer (a-e)/f.
Another example would be an original slope of -2/5 has a perpendicular slope of 5/2. Notice how the two slopes -2/5 and 5/2 multiply to -1. This is true of any pair of perpendicular lines where neither line is vertical.
1. Convert percent into decimal (it will help)

2. Convert Decimal to fraction
total number of student in the data set in the dataset is 90
Step-by-step explanation:
4x + 8y = 40
4x + (8×0.8) = 40
4x + 6.4 = 40
4x = 33.6
4x÷4 = 33.6 ÷ 4
x = 8.4