Question 824153
To picture the rooms, the areas of the ceilings are
10 x 12 ft2
If you measure from floor to ceiling, the height
of each room is 8 ft
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That tells you that each room has two walls
that are 8 x 12 ft2
and two walls that are 8 x 10 ft2
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The ceilings are each 10 x 12 ft2
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So, for one of the 3 rooms, you have:
Area[1] = {{{ 2*8*12 + 2*8*10 + 10*12 }}}
Area[1] = {{{ 192 + 160 + 120 }}}
Area[1] = {{{ 472 }}} ft2
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The total area of the 3 rooms is:
Area[3] = {{{ 3*472 }}}
Area[3] = {{{ 1416 }}} ft2
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You have to subtract the areas of the window
and a door in each room:
Area[1'] = {{{ 4*5 + 3*7 }}}
Area[1'] = {{{ 41 }}}
The total area to subtract for the 3 rooms is:
Area[3'] = {{{ 3*41 }}}
Area[3'] = {{{ 123 }}}
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The area that must be painted is:
Area = {{{ 1416 - 123 }}}
Area = {{{ 1293 }}}
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To find the number of cans of paint needed:
{{{ 1293 / 250 = 5.172 }}}
They won't sell you part of a can of paint,
so you need 6 cans of paint