SOLUTION: Maria is standing beside a 15-foot flagpole. She is 4.5 feet tall and casts a 7.5-foot shadow. What is the length of the flagpole's shadow?

Algebra ->  Proportions -> SOLUTION: Maria is standing beside a 15-foot flagpole. She is 4.5 feet tall and casts a 7.5-foot shadow. What is the length of the flagpole's shadow?      Log On


   

Question 139535: Maria is standing beside a 15-foot flagpole. She is 4.5 feet tall and casts a 7.5-foot shadow. What is the length of the flagpole's shadow?
Found 2 solutions by MathLover1, solver91311:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
let a 15-foot flagpole be f
Maria is h=4.5+feet tall and casts a s=7.5-foot shadow
the length of the flagpole's shadow x
then:

f%3Ax+=+s%3Ah
15%2Fx+=+7.5%2F4.5
15%2A4.5=+x%2A7.5
15%2A4.5%2F7.5+=x
x+=67.5%2F7.5
highlight%28x+=+9%29
check:
15%2F9=+7.5%2F4.5
1.6666666666666666666666666666667=+1.6666666666666666666666666666667

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
The height of the object and the length of the shadow are proportional, so:

The length of the flagpole shadow divided by the length of Maria's shadow is equal to the height of the flagpole divided by Maria's height.

x%2F7.5=15%2F4.5

So just solve for x. Hint: Cross-multiply and then divide by the coefficient on x.