#1

#7

#8

#4**+4 **

volume of cuboid: 14*28*17

volume of cuboid: 6664cm^3

radius=7

area of semi circle=pi*r^2/2

area of semi circle=pi*7^2/2

area of semi circle=76.96902001cm^2

are of cross section*length

76.96902001cm^2*28=2155.13256cm^3

2155.13256cm^3+6664cm^3=8819.13256cm^3

lynx7
Feb 12, 2018

#9**+4 **

The priism is easy...it's just W * L * H = 14 * 28 * 17 = 6664 cm^3 (1)

For the half-cylinder...the volume is

(1/2 pi * r^2 * height

The "height" is the length of the lunchbox = 28 cm

We neeed to be careful with r ...it equals 14/ 2 = 7cm

So the volume of the half-cylinder is

(1/2) pi * (r^2) * h =

(1/2) pi (7)^2 * 28 = 2155.13 cm^3 (2)

Add (1) and (2) = 8819.13 cm^3

CPhill
Feb 12, 2018