Copyright © Swun Math Grade 8 Unit 1 Lesson 5 P TEAnswer Key
Extension Activity
Answers may vary. Sample response: Estimating the value of the decimal would give us an easier number to
deal with when calculating formulas. On the other hand, at times it is very important to be exact, for example a
non-exact calculation may result in a vaccination that is not as effective. In this case, a fractional
representation of a repeating decimal would be more effective.Homework
- Two equations to represent 0.777...:
- x = 0.777...
- 10x = 7.77...
Solve:
10x – x = 7.777... - 0.777...
9x = 7
x =^79Answer:^79- Two equations to represent 0.0833...:
- 100x = 8.333...
- 1000x = 83.33...
Solve:
1000x – 100x = 83.33... - 8.333...
900x = 75
x = 90075 →→900 7575 75÷÷ 121Answer: 121- Two equations to represent 0.0909...:
- x = 0.0909...
- 100x = 9.09...
Solve:
100x – 1x = 9.09... - 0.0909...
99x = 9
x =^9991
99 99 9 11
→→÷
÷Answer: 1114. 7
6
Two equations to represent 1.1666...:- 10x = 11.666...
- 100x = 116.66...
Solve:
100x – 10x = 116.66... - 11.666...
90x = 105
x =^10590 →→105 1590 15÷÷ 67Answer:^7
6or 1^16- Two equations to represent 0.343434...:
- x = 0.343434...
- 100x = 34.3434...
Solve:
100x – 1x = 34.3434... - 0.343434...
99x = 34x =^34
99
Answer:^3499- Two equations to represent 0.0151515...:
- 10x = 0.151515...
- 1000x = 15.1515...
Solve:
1000x – 10x = 15.1515... - 0.151515...
990x = 15
x =15
990 =15÷ 15
990 ÷15=1
66Answer: 661