11 I wish to repaint the walls of my garage. It is 3 metres high, 4 metres wide and 9 metres deep. I
shall not need to paint the electronic door which covers one 3 x 4 metre end, nor the window, which
is 2 metres wide and 1 metre high, nor the rear door which is 1 metre wide and 2 metres high. 1
litre of paint covers 3 square metres.
How many 1 litre tins will be needed to complete the painting?

45 tins will be needed.

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To solve this question, the surface area of a rectangular prism need to be found. With the surface area that will be painted, it is possible to find the number of 1 liter tins that will be needed.

Surface area:

The surface area of a rectangular prism with height h, width w and depth d is:

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Total surface area:

Thus, the total surface area, in square meters, will be:

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Area painted:

These following areas will be removed:

Thus, the total area painted will be:

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How many tins?

Thus:

Rounding up:

45 tins will be needed.

A similar question is given at link

33 tins

Step-by-step explanation:

4*9=36 m^2 - the ceilling

2*(9+4)*3 the walls

you have to paint 4*9+2*(9+4)*3-(3*4+2*1+1*2)=36+78-16=98 m^2

98<99

99:3=33 l will be needed

the ratio of grapes to blueberries she should use is 12: 3

step-by-step explanation:

if mandie is making 15 cups of fruit salad, the ratio of grapes to blueberries she should use is 12: 3.