G8

Copyright © Swun MathCopyright © Swun Math (^) Grade 8 Unit 3 Lesson 7 P TE

Challenge Problems

Directions: Solve. You will notice that these are longer and more complex, but still follow the

same patterns as the previous ones.

1. (2.15 × 10^10 ) ÷ (4 × 10^7 ) – (4.6 × 10^2 )

Solution:

• (2.15 × 10^10 ) ÷ (4 × 10^7 ) – (4.6 × 10^2 )


• 2 .15 ⋅10

10

4⋅ 10^7 −(4.6⋅^10

(^2) )

• 
  
  
  
  2. 415 ⋅^10
  
  
  
  

10

107 −(4.6⋅^10

(^2) )

• 0.5375 × 10^10 –7 – (4.6 × 10^2 )

• (0.5375 × 10^3 ) – (4.6 × 10^2 )

• (5.375 × 10^2 ) – (4.6 × 10^2 )

• (5.375 – 4.6) × 10^2

• 0.775 × 10^2

Answer: 7.75 × 10^1

2. (3.3 × 10^3 ) × (4.1 × 10^5 ) + (7.6 × 10^8 )

Solution:

• (3.3 × 103 )×(4.1 × 105 )+(7.6 × 108 )


• (3.3 × 4.1)×( 103 × 105 )+(7.6 × 108 )


• (13.52 × 10 3+5)+(7.6 × 108 )


• (13.52 × 108 )+(7.6 × 108 )


• (13. 52 + 7.6) × 108


• 21.13 × 108

Answer: 2. 113 × 109

Extension Activity

* MP1: Make sense of the problem and persevere in solving it.

* MP4: Apply mathematics in everyday life.

Using only the digits 1-9, create as many true equations as possible. For each equation, the

digits are only to be used once.

(▭.▭ × 106 ) + (▭.▭ × 106 ) = ▭.▭ × 106

(▭.▭ × 106 ) ─ (▭.▭ × 106 ) = ▭.▭ × 106