Page 183 - TB_5B

Unit 28. Cover the Surface with Chocolate b. D

P. 106~107 A

The surface area is BC
(6 10) 2 (10 8) 2 (6 8) 2 376 cm2. E

The difference can be found by comparing the Surface area = A B C D E
newly made surfaces of the cake pieces.
2 pieces of bread, which are of the same = 24 42 56 70 24
shape(rectangular prism) and size are cut to = 216 (cm2)
make 4 pieces of cake.
The area of each surface is the same size. 2 . a . 48 b . 108
So only the newly made surfaces need to be
compared. The surfaces of the pieces of cake Activity 3 P. 112~113
that are in the shape of triangular prisms is
larger. 24, 24

1 . a . Surface area (6 5 3) 2 28 (in.2)

Activity 1 P. 108~109 b . Surface area (15 9 9) 2 66 (in.2)

1 . a . Surface area (A B C) 2 2. a. b. c.
(30 25 30) 2
85 2
170 (cm2)

b . Surface area ( A B C ) 2 Unit 29. How Many Cubes Are Used?
2
(16 16 16) P. 114~115
48 2 96 (ft2) ]
96 (ft2)
[ A 6 16 6

c . Surface area (A B C) 2 12, 12
(24 48 32) 2 27, 27
104 2 48, 48
208 (in.2) 15, 15
18, 18
Activity 2 P. 110~111 14, 14
1. a. 20, 20

A Activity 1

P. 116~117

B CD 5, 4, 3, 60
E
1 . a . 45 b . 24 c . 27

Surface area = A B C D E 2 . a . 36 b . 24 c . 210

= 6 24 18 30 6 3 . a . Volume 10 5 10 500 (cm3)
= 84 (cm2)

b . The cereal box.

c . Candy box, cracker box, cereal box.

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