Given :
Nathan smiled at 50 people one day and recorded that 36 people smiled back at him.
To Find :
How many people should Nathan expect to return a smile if he smiles at 650 people over a period of time.
Solution :
Ratio of people smiled by total number of people is :

Now, it is given that we have to use the given conditions.
Therefore, ratio will be same :

Therefore, number of smiles Nathan expect to return is 468.
Hey!
Hope this helps...
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The first thing we know is that all the answers equal 99, so we cannot cross any answer off, however, what we want to know is what answer (after distribution) looks like 36 + 63...
A.) 11(3 + 6) > 33 + 66
Does 33+66 look like 36+63?
NO
B.) 9(4 + 7) > 36 + 63
Does 36+63 look like 36+63?
YES
C.) 11(4 + 5) > 44 + 55
Does 44+55 look like 36+63?
NO
D.) 3(15 + 18) > 45 + 54
Does 45+54 look like 36+63?
NO
So...
The answer is: B.) 9(4 + 7)
The inscribed circle has its center at the point of intersection of the angle bisectors, which also happen to be the medians. Hence the altitude of the triangle is 3 times the radius, or 12 inches.
The side length of this triangle is 2/√3 times the altitude, so the area is
... Area = (1/2)·b·h = (1/2)·(24/√3 in)·(12 in)
... Area = 48√3 in² ≈ 83.1384 in²
Basically 1/2 equals 2 and times x equals 2x. X is a variable an unknown number so 2x +4 and that's how you get your answer