Question 410872
Suppose you have two cans of paint that can cover a total of 800 sq.ft.
 Find the radius of the largest circle you can paint. Round to the nearest tenth of a foot."
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You know the largest circle you can paint will be 800 sq/ft
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You know the Area of circle formula:  {{{pi*r^2}}} = A
therefore
{{{pi*r^2}}} = 800; find r
Divide both sides by pi and you have
{{{r^2}}} = {{{800/pi}}}
which is
{{{r^2}}} = 254.648; (divided 800 by pi using a calc)
Find the square root of both sides
r = {{{sqrt(254.648)}}}
Find this also on a calc
r = 15.96 rounded to 16 ft is the radius of the circle
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YOu can prove this to yourself
Find the area of circle using calc: {{{pi*16^2}}} = 804, not 800 because we rounded up 16 ft
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Did explain things to you?