6.7*6.7 to find the surface area of the base which is 44.89
4*1/2*10.1*6.7 to fix the surface area of all four triangular faces which is 135.34
Plus them together 44.89+135.34 which is 180.23
The common difference is a₂-a₁=14-9=5.
The fourth term is the third term plus the common difference -> 19+5=24.
The answer is B.
I'll do the first two problems to get you started. All problems shown will use the same formula.
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Problem 4
The formula to use is
C = 100*(B-A)/A
where
A = old value
B = new value
C = percent change
In this case, A = 12 and B = 36, so
C = 100*(B-A)/A
C = 100*(36-12)/12
C = 100*(24/12)
C = 100*2
C = 200%
We have a 200% increase. It is an increase because the value of C is positive.
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Problem 5
Use the same formula as in the previous problem. This time,
A = 75 is the old value
B = 25 is the new value
C = 100*(B-A)/A
C = 100*(25-75)/75
C = 100*(-50/75)
C = 100*(-2/3)
C = -66.6667%
C = -66.7%
The value of C is negative, so we have a percent decrease of roughly 66.7%
Let y = (b)ˣ
1) if b> 0, then growth, whatever the value of x>0
2) if b< 0, then decay, whatever the value of x >0
3) if b<0, then decay, whatever the value of x >0
4) if b<0, then growth, whatever the value of x <0