11. If you want to enlarge a square with area 36 square inches by a factor of 3, what would be its new perimeter?

a. 18 inches
b. 24 inches
c. 324 inches
d. 8 inches
e. 72 inches

e. 72 inches

Step-by-step explanation:

Well, firstly to find the lengths of the sides, we would have to find the square root of 36 (which is 6, as 6x6=36).

Now, if we enlarge the square by SF 3, the new side lengths would be 6x3=18 inches. That is only one side.

Now we know the length of one side, we can do 18x4 (because as we all know, squares have 4 sides) to find the perimeter.

18x4=72 inches. This means the answer is option e.

answer: ratio of volume of cone (with 3 times the height and equal diameter) to volume of cylinder is 2 to 1. the value of π is not used.

step-by-step explanation:

radius is diameter/2 = 4.

area of circle is π r^2.

volume of cylinder is height × area of base = hπr^2 = 3(4^2) π = 48π cubic inches.

not knowing the formula for volume of cone, i calculate it using calculus (which is for calculating things).

volume of cone is integral 0 to h area(y) dy. area(y) is π r(y)^2. r(y) runs r to zero as y runs zero to h, r(0) = r, r(h) = 0.

r(y) = r - r/h y

area(y) = π (r - r/h y)^2 = π (r^2 - 2r^2y/h + r^2y^2/h^2) = π r^2(1-2y/h+y^2/h^2)

antiderivative area(y) = π r^2 (y-y^2/h+y^3/(3h^2))

integral 0 to h = π r^2(h-h^2/h+h^3/(3h^2) - (0)) = π r^2(h - h + h/3) = π r^2(h/3) = π/3 r^2 h

volume of this cone is π/3(4^2)18 cubic inches.

= 6 16 π = 96π cubic inches.

cone has twice the volume, 96/48.

cone height is 6 times the cylinder.

ratio of volume formula: π r^2 cancels.

cone over cylinder ratio is 6h/3 to h, 2 to 1.

i believe your answer is 99.7% of 7-year-old children are between 46.6 inches and 49.5 inches tall.