Any suggestions as to how to solve this math problem?

Question

A certain recipe makes enough batter for exactly 8 circular pancakes that are each 10 inches in diameter. How many circular pancakes, each 5 inches in diameter and of the same thickness as the 10-inch pancakes, should the recipe make?

Answer 1

so the area of a circle is (pie)(radius)^2

so for the first one, you'd have 25 pie

in the second one, you'd have 6.25 pie

so i don't have a calculator, but find out how much batter he has first (so the guy can make 8 pancakes that use 25 pie units of batter... so thats 200 pie units of batter in total)

now divide 200 pie by 6.25 pie and you get.... 32?

32 pancakes?

Answer 2

Work out the area of one 10 inch pancake

Multiply by eight

Divide by the area of one 5 inch pancake

Round down to a whole number

Answer 3

Each pan cake have volume pi *r^2*h

r=radius

h=thickness

if radius =10 inch

pi*10^2*h=100*3.14*h=314h

total 8 number cale,volume = 8*314h=2512h

Now number of pan cake of 5 inch dia=x

each pancake have volume

pi*5^2*h=3.14*25*h=78.5h

x no pan cake have volume

x*78.5h

this is equal to 2512h

2512h=x*78.5h

or x=2512/78.5= 32 number

Answer 4

area of 10 inch pancake= 25 pi

8-10 inch pancakes = 200 pi

area of 5 inch pancake = 6.25 pi

200 pi / 6.25 pi = 32