Page 53 - RME-Based Bilingual E-Module

LEARNING ACTIVITIES 3

Activities 3.4 Examples

Let’s Learn!

Problem of Sphere Surface Area
Aisyah has a globe with 35 cm of diameter. Aisyah will cover the globe

with transparent plastic so it doesn't get dusty. Determine the minimum
plastic area required by Aisyah!

Solution:

Known : d = 35 cm  r = ½ x 35 = 35/2 cm
Asked : Minimal Plastic Area = Surface Area of Sphere

Answer : Surface Area of Sphere = 4  r
2
2
= 4 x 22/7 x (35/2)
2
= 3.850 cm
2
So, the minimum plastic area required by Aisyah is 3.850 cm .

Problem of Sphere Volume
Pempek Zhafira sells at least 500 pempek adaan every day. The diameter

of pempek adaan is 6 cm. How many kilograms of dough are made?
3
(1 cm = 0,9 gram)

Solution:

Known : n = 500
d = 6 cm  r = ½ x 6 = 3 cm
Asked : Many kilograms of dough

Answer : Volume of a pempek adaan = Volume of sphere
3
= 4/3  r
= 4/3 x 3,14 x 3 x 3 x 3

3
= 113,04 cm
So, dough are 113,04 x 500 x 0,9 = 50.868 gram = 50,9
kilogram.

RME-BASED BILINGUAL E-MODULE— 20