B)
C)
6. A)
Both rectangular prisms have the volume of 200cm.
B)
Both rectangular prisms have the volume of 10.5 m3.
8.
The need to put 24.3m3 of water in the pool.
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Jumbo:
r= d÷2 V=(pi.r.r)x h
r= 20÷2 V=(3.14x10x10)x40
r=10cm V=314 x 40
V=12'560cm³
Popcorn Lover's:
r= d÷2 V=(pi.r.r)x h
r= 30÷2 V=(3.14x15x15)x20
r= 15cm V= 7065 x 20
V= 14'130cm³
Martha should buy the popcorn lover's one because it has a greater volume than the Jumbo one.Popcorn Lover's volume is 14,130cm³ and Jumbo's 12,560cm³.
Chapter 7.4

Outside;
r=d÷2 V=(pi.r.r)x h
r= 1÷2 V=(3.14x0.5x0.5)x10
r=0.5m V= 0.785 x 10
V= 7.85m³
Inside;
r= d÷2 V=(pi.r.r)x h
r= 0.8÷ 2 V=(3.14x0.4x0.4)x10
r= 0.4m V=0.5024 x 10
V= 5.024m³
You Subtract the volume of the inside from the volume of the outside.
7.85m³ - 5.024m³ = 2.826m³
The volume of concrete needed to make the culvert is 2.826m³