Answer:
17
Step-by-step explanation:
f(x) = 3x + 2
Let x=5
f(5) = 3*5 + 2
Multiply first
= 15+2
Then add
= 17
The least-square regression line has a slope of:
m=(nΣxy-ΣyΣx)/(nΣx²-ΣxΣx)
and a y-intercept of:
b=(Σy-mΣx)/n
In this case: n=7, Σxy=4899, Σy=391, Σx=85, Σx²=1153 so
m=(7(4899)-391*85)/(7(1153)-85*85))=1058/846
b=(391*846-85*1058)/(7*846)=34408/846
So the line of best fit is:
y=(1058x+34408)/846 and if we approximated this as your answers see to have done....
y=1.25x+40.67
<span>5 = 15
---------
8 = x
cross multiply
5x =120
5x÷5 = 120÷5
x = 24
Check
5/8 = 15/24
.625 = .625
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Answer:
A
Step-by-step explanation: