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PLZZZ!!!!!! HELP

A pillar candle is shaped like a cylinder with a radius of 1.5 inches. The candle holds 123 cubic inches of wax. How tall is the candle? Use 3.14 for pi. Round your answer to the nearest hundredth.
12.50 in
15.76 in
17.41 in
18.76 in

2 Answers

5 votes
17.41- The formula for the volume of a cylinder is pi radius squared times height. (i.e. the area of the base times the height).  You have pi 1.5 squared times height =123.  Then you square it so you have 2.25 pi h= 123. then you have 7.065h=123. The you do algebra and you get 17.409, and round it to 17.41.
User Return
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Answer: The correct option is (C) 17.41 in.

Step-by-step explanation: Given that a pillar candle is shaped like a cylinder with a radius of 1.5 inches and the candle holds 123 cubic inches of wax.

We are to find the height of the candle.

We know that the VOLUME of a cylinder with radius r units and height h units is given by


V=\pi r^2h.

For the given cylindrical candle, we have

radius, r = 1.5 inches

and

VOLUME, V = 123 cubic inches.

height, h = ?

We have


V=\pi r^2h\\\\\Rightarrow 123=3.14* (1.5)^2* h\\\\\Rightarrow h=(123)/(3.14*2.25)\\\\\\\Rightarrow h=(123)/(7.065)\\\\\Rightarrow h=17.4097.

Rounding to nearest hundredth, h = 17.41 in.

Thus, the Candle is 17.41 inches tall.

Option (C) is CORRECT.

User Peter Rakmanyi
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