SOLUTION: A telephone pole casts a shadow that is 30 feet long. At the same time, a man standing nearby who is 6 feet tall casts a shadow that is 4 feet 6 inches long. How tall is the teleph

Question 1172121: A telephone pole casts a shadow that is 30 feet long. At the same time, a man standing nearby who is 6 feet tall casts a shadow that is 4 feet 6 inches long. How tall is the telephone pole to the nearest foot?
When I solved this I got 40 feet. I'm not sure if that is correct, but here is the steps I took:
1. Converted 4ft into 48in by multiplying 4x12 then I added 6, Total: 54in.
2. Then I took 6x12 and got 72 and took 30x12 and got 360.
3. The proportion formula I used was height / shadow = height / shadow.
4. I plugged in the numbers 54 / 72 = x / 360 and cross multiplied and divided
5. Result, I got 480 and divided by 12 to convert back into feet since that is what the question wanted.
6. As a final answer I got 40

Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website!
Draw your diagram showing the similar triangles.
Tallness of pole is to 6 foot man as 30 feet shadow is the foot shadow of man.

.
.
You should be able to handle the needed steps.
40 feet tall is correct.
Answer by MathTherapy(10552) (Show Source): You can put this solution on YOUR website!

A telephone pole casts a shadow that is 30 feet long. At the same time, a man standing nearby who is 6 feet tall casts a shadow that is 4 feet 6 inches long. How tall is the telephone pole to the nearest foot?
When I solved this I got 40 feet. I'm not sure if that is correct, but here is the steps I took:
1. Converted 4ft into 48in by multiplying 4x12 then I added 6, Total: 54in.
2. Then I took 6x12 and got 72 and took 30x12 and got 360.
3. The proportion formula I used was height / shadow = height / shadow.
4. I plugged in the numbers 54 / 72 = x / 360 and cross multiplied and divided
5. Result, I got 480 and divided by 12 to convert back into feet since that is what the question wanted.
6. As a final answer I got 40

Your answer is correct, but it involves too many UNNECESSARY calculations!
You're right in using a proportion to solve, but when you look at the man's shadow, you should see that it's easier to keep it in feet, since 4 feet, 6 inches =
<====== Keeping with your proportion, and by letting "x" be the pole's height.

4.5x = 6(30) ------ Cross-multiplying
Pole's height, or
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