A pyramid with a rectangular base is stacked on top of rectangular prism. The height of the composite figure is 12 inches. The lengths of the rectangular base are 7 inches and 3 inches. The height of the rectangular prism is 4 inches.
What is the volume of the composite figure?

140 cubic inches
147 cubic inches
168 cubic inches
196 cubic inches

Step-by-step explanation:

140 cubic inches

140 cubic inches

Step-by-step explanation:

The formula for determining the volume of a rectangular base pyramid is expressed as

Volume = 1/3 × base area × height

From the information given,

Length = 7 inches

Width = 3 inches

Base area = 7 × 3 = 21 square inches

Height = 12 - 4 = 8 inches

Volume = 1/3 × 21 × 8 = 56 cubic inches

The formula for determining the volume of a rectangular prism is expressed as

Volume = Length × width × height

Volume = 7 × 3 × 4 = 84 cubic inches

Volume of the composite figure is

56 + 84 = 140 cubic inches

b

step-by-step explanation:

the total estimated nappy use.=10,500,000

step-by-step explanation:

given that on an average the average baby uses 3528 napkins.

in a particular year 2014, the number of births were 299697 in new south wales.

rounding off the number of births to the nearest hundred thousand we have

no of birtsh = 300000

also rounding off the average usage to nearst thousand we get

average use of a baby = 3500

hence total number of nappy estimated to be used = 3500x300000

= 10,500,000

answer is 10,500,000 nappies