EXERCISE MATH ABOUT CUBE AND CUBOID

1. a. Fine the surface area:                                   E                               K

 (lw + lh + hw)

C

2 (9.2 + 9.8 + 8.12                                        8 cm       A                              M

2 (108 + 72 + 96)                                              N

2 (276) = 552 cm^{2                                                         12 cm}

b. Find the volume:                                                       D           9 cm        H

l x w x h

12 . 9 . 8 = 864 cm²

c. Find the length of space diagonal:

NH =                                                   E                                  K

= 15 cm                                                                        A                            M

C

EH  =

=                                                 N                    

= 17 cm                                                                      D                                  H

d. Find AC:

AC =

            =

            = 17 cm

e. The length of AK

AK =

            =

            = 15 cm

f. Area of diagonal plane NHME

NHME = NH x HM

= 15 x 8

= 120 cm²

g. Area DCKA

DCKA  = AD x DC

= 8 x 15

= 120 cm²

h. Diagonal of diagonal plane DCKA

Diagonal DCKA =

 =

 = 17 cm

i. Diagonal of diagonal plane DHKE=

KH =

=

=

DK =

=

= 17 cm

j. Diagonal of diagonal plane AHCE

CA = gggfffg

=

= 17 cm

k. Yes, is it.

2. Surface area of a cube 54 cm²

6 (s²)  = 54

s²       = 9

s        = 3

- Volume =

s . s . s = 3 . 3 . 3

= 27 cm³         

- Space diagonal

=

=

=

= 3  cm

- Face diagonal

=

=

= 3  cm

- Area of diagonal plane

= Face diagonal x s

= 3  cm x 3

= 12.73 cm²

3. Cuboid dimensions = 2 cm x 3 cm x 4 cm

- Surface area

= 2 (lw + lh + hw)

= 2 (4.3 + 4.2 + 2.3)

= 2 (12 + 8 + 6)

= 2 (26)

= 52 cm²

- Cuboid volume

= l . w . h

= 4 . 3 . 2

= 24 cm³

4. The length of wire

= 4 (l . w . h)

= 4 (6 + 3 + 4)

= 4 (13)

= 52 cm

5. The length of wire is 4 m will be made frames of cube of dimensions 5 cm . 2 cm . 7 cm

a. Determine the number of frames that can be made

   frames remains  frames

b. Determine the length of wire remains

 x the length of frames

 x } =  x 56

= 8 cm