Answer:
12a. 471.2 cm²
12b. 60 m²
Step-by-step explanation:
Part A.
The surface area of each figure is the sum of the end area and the lateral area.
<u>cylinder</u>
S = (2)(πr²) +2πrh = 2πr(r +h)
S = 2π(5 cm)(5 cm +10 cm) =150π cm² ≈ 471.2 cm²
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<u>triangular prism</u>
S = (2)(1/2)bh + PL . . . . b=triangle base; h=triangle height; P=triangle perimeter; L=length of prism
S = (4 m)(1.5 m) + ((4 + 2·2.5) m)(6 m) = (6 + 54) m² = 60 m²
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Part B.
Surface area is useful in the real world wherever products are made from sheets of material or wherever coverings are applied.
Carpeting or other flooring, paint, wallpaper are all priced in terms of the area they cover, for example.
The amount of material used to make containers in the shapes shown will depend on the area of these containers (and any material required for seams).
Let x be the amount of cement and y be the amount of sand. If <span>the ratio of cement to sand for mortar is 1:3, then
and y=3x.
</span>
So, if <span>Sandy puts in x=7 shovels of cement, then she puts
shovels of sand.
</span><span>
</span><span>
Answer: 21 shovels of sand.
</span>
5’3 is 63 inches since her brother is 1/3 larger so 63/3= 21 inches
Answer:
I hope it will help you..
