Math
posted by Jenny on .
A person is standing next to a flag pole.The person is 6ft tall.She casts a shadow 10 ft long.The flag pole casts a shadow of 45 ft long.How tall is the flag pole.

Let's use a proportion. Let x = the height of the flag pole.
6/10 = x/45
Cross multiply.
10x = 270
x = 27 
This is a proportion problem. There are two ways to solve this.
The 1st way, my preferred one, is to take 6 and 10 as a ratio. 6:10 simplyfied is 3:5. So, 45 / 5 is equal to 9, so 3 * 9 = 27.
That may be a little confusing sometimes so there is a second way. Take 6/10. It is equal to x / 45. (X being the flagpole length). If you crossmultiply you get 10x = 6 * 45. Simplify and you get x = 270 / 10 or 27. 
i need help to one simular to this one. ok if the flag pole is 15 feet tall and 8 feet long and the boy is 5 feet tall. what proportion can be made to find the lenght of his shadow?