The circumference of a circle is 9 pi.What is the area,in square inches,of a circle?Express your answer in terms of pi.
1 answer:
Answer:
20.25π
Step-by-step explanation:
The circumference (C) of a circle is calculated using the formula
C = 2πr ← r is the radius
given C = 9π, then
2πr = 9π ( divide both sides by 2π )
r = ( cancel the π on numerator/denominator )
= 4.5
The area (A) of a circle is calculated using the formula
A = πr² = π × 4.5² = 20.25π
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The mass of brick is 2478 gram
<em><u>Solution:</u></em>
A brick is in the shape of a rectangular prism with a length of 8 inches, a width of 3.5 inches, and a height of 2 inches
Length = 8 inches
Width = 3.5 inches
Height = 2 inches
<em><u>The volume of rectangular prism is given as:</u></em>
Thus volume of brick is 56 cubic inches
<em><u>Convert inches to centimeter</u></em>
1 inch = 2.54 centimeter
Therefore,
56 cubic inches = 56 x 2.54 x 2.54 x 2.54 cubic centimeter
56 cubic inches = 917.676 cubic centimeter
Thus, we get,
volume = 917.676 cubic centimeter
The brick has a density of 2.7 grams per cubic centimeter
Density = 2.7 grams
<em><u>The mass of brick is given by formula:</u></em>
<em><u>Substituting the values we get,</u></em>
Thus mass of brick is 2478 gram
Answer:
Total 25.45 hours will be taken to empty the pool.
Step-by-step explanation:
Time taken by large pumpkin to empty the pool=40 hours
Time taken by the smaller pumpkins to empty the pool=70 hours
Amount of pool emptied by large pumpkin in one hour=
Amount of pool emptied by small pumpkin in one hour=
Amount of pool emptied in one hour if both pumpkins work together=
+
=
Therefore, the no. of days will be the reciprocal of the amount of work done in one hour ie .
Total 25.45 hours will be taken to empty the pool.