24 * 3/4 = 18
The radius of smaller cone is 3/4 the radius of original cone, so since these cones are similar, height must also be 3/4 times smaller.
So since radius is squared and we also multiple the height (V = 1/3 π r² h),
the volume of smaller cone would be 3³ / 4³ = 27 / 64 times smaller
So we have 1920 * (27 / 64) = 810.
Final answer: B
For a width of 25, the length will also be 25, so the area is 25² = ...
625.
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The rule is
area = width×(50 -width)
This might be wrong but I got 120/1008
D ) x = 0 and x = 3 π / 4
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