this is from 15 testset.
on an aerial photograph, the surface of a pond appears as circular region of radius 7/16 inch. if a distance of 1 inch on the photogragh corresponds to an actual distance of 2 miles, which of the following is the closest estimate of the actual surface area of the pond, in square miles.
a,1.3
b,2.4
c,3.0
d,3.8
e,5.0
Strange question. help pls.
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In this problem, you need to convert photo scale into the actual sclae. i.e. the radius of photo to the radius of actual place in the air.
s0, 7/16*2=14/16.
knowing the formula of the area of the cirlce - (pi)r^2
the area will be - 196/256(pi) ( pi=3.14 so it would be approximately 3)
after simplification - 49/64*(pi), round both numerator and denominator to the closest number.
50/65*3=10/13*3=30/13, approximately 2.3 smth.
so the answer should be b.
s0, 7/16*2=14/16.
knowing the formula of the area of the cirlce - (pi)r^2
the area will be - 196/256(pi) ( pi=3.14 so it would be approximately 3)
after simplification - 49/64*(pi), round both numerator and denominator to the closest number.
50/65*3=10/13*3=30/13, approximately 2.3 smth.
so the answer should be b.