<< Chapter < Page Chapter >> Page >

Mathematics

Decimal fractions

Educator section

Memorandum

13.4

a) 2 60 100 size 12{ { { size 8{"60"} } over { size 8{"100"} } } } {} 2,60
b) 13 625 1000 size 12{ { { size 8{"625"} } over { size 8{"1000"} } } } {} 13,625
c) 17 75 100 size 12{ { { size 8{"75"} } over { size 8{"100"} } } } {} 17,75
d) 23 875 1000 size 12{ { { size 8{"875"} } over { size 8{"1000"} } } } {} 23,875
e) 36 8 10 size 12{ { { size 8{8} } over { size 8{"10"} } } } {} 36,8

13.5 a) 0,83

  1. 0,2857142
  2. 0,8125
  3. 0,4

13.6

9 2 size 12{ { { size 8{9} } over { size 8{2} } } } {} 11 2 size 12{ { { size 8{"11"} } over { size 8{2} } } } {} 325 100 size 12{ { { size 8{"325"} } over { size 8{"100"} } } } {} 43 5 size 12{ { { size 8{"43"} } over { size 8{5} } } } {} 201 8 size 12{ { { size 8{"201"} } over { size 8{8} } } } {} 4056 1000 size 12{ { { size 8{"4056"} } over { size 8{"1000"} } } } {} 199 5 size 12{ { { size 8{"199"} } over { size 8{5} } } } {}
4 1 2 size 12{ { { size 8{1} } over { size 8{2} } } } {} 5 1 2 size 12{ { { size 8{1} } over { size 8{2} } } } {} 3 25 100 size 12{ { { size 8{"25"} } over { size 8{"100"} } } } {} 8 3 5 size 12{ { { size 8{3} } over { size 8{5} } } } {} 25 1 8 size 12{ { { size 8{1} } over { size 8{8} } } } {} 4 56 1000 size 12{ { { size 8{"56"} } over { size 8{"1000"} } } } {} 39 4 5 size 12{ { { size 8{4} } over { size 8{5} } } } {}
4,5 5,5 3,25 8,6 25,125 4,056 39,8

14. a) 0,3

  1. 0,6
  2. 0,23

Leaner section

Content

Activity: more revision [lo 1.4.2, lo 1.10, lo 2.3.1, lo 2.3.3]

We can convert proper fractions to decimal fractions in this way:

13.2 Did you know?

We can also calculate it in this way:

13.3 Which of the methods shown above do you choose?

Why?

13.4 Complete the following tables:

13.5 Use the division method as shown in 13.2 and write the following fractions as decimal fractions:

a) 5 6 size 12{ { {5} over {6} } } {} ........................................................................... ...........................................................................

...........................................................................

b) 2 7 size 12{ { {2} over {7} } } {} ........................................................................... ...........................................................................

...........................................................................

c) 13 16 size 12{ { {"13"} over {"16"} } } {} ........................................................................... ...........................................................................

...........................................................................

d) 4 9 size 12{ { {4} over {9} } } {} ........................................................................... ...........................................................................

...........................................................................

13.6 Can you complete the following table??

Improper fraction 9 2 size 12{ { { size 8{9} } over { size 8{2} } } } {} 45 5 size 12{ { { size 8{"45"} } over { size 8{5} } } } {}
Mixed Number 5 1 2 size 12{5 { { size 8{1} } over { size 8{2} } } } {} 25 1 8 size 12{"25" { { size 8{1} } over { size 8{8} } } } {} 39 4 5 size 12{"39" { { size 8{4} } over { size 8{5} } } } {}
Decimal fraction 3,25 4,056

14. BRAIN-TEASERS!

Write the following fractions as decimal fractions. Try to do these sums first without a calculator!

a) 1 3 size 12{ { {1} over {3} } } {} ........................................................................... ...........................................................................

...........................................................................

b) 2 3 size 12{ { {2} over {3} } } {} ........................................................................... ...........................................................................

...........................................................................

c) 23 99 size 12{ { {"23"} over {"99"} } } {} ........................................................................... ...........................................................................

...........................................................................

15. Do you still remember?

We call 0,666666666 . . . a recurring decimal . We write it as 0, 6 size 12{0, {6} cSup { size 8{ cdot } } } {} .

0,454545 . . . is also a recurring decimal and we write it as 0, 4 5 size 12{0, {4} cSup { size 8{ cdot } } {5} cSup { size 8{ cdot } } } {} .

We normally round off these recurring decimals to the first or second decimal place, e.g.: 0, 6 size 12{0, {6} cSup { size 8{ cdot } } } {} becomes 0,7 or 0,67 and 0, 4 5 size 12{0, {4} cSup { size 8{ cdot } } {5} cSup { size 8{ cdot } } } {} becomes 0,5 or 0,45

16. Time for self-assessment

  • Tick the applicable block:
YES NO
I can:
Compare decimal fractions with each other and put them in the correct sequence.
Fill in the correct relationship signs.
Round off decimal fractions correctly to:
  • the nearest whole number
  • one decimal place
  • two decimal places
  • three decimal places
Convert fractions and improper fractions correctly to decimal fractions.
Explain what a recurring decimal is.

Assessment

Learning Outcome 1: The learner will be able to recognise, describe and represent numbers and their relationships, and to count, estimate, calculate and check with competence and confidence in solving problems.

Assessment Standard 1.4: We know this when the learner recognises and uses equivalent forms of the rational numbers listed above, including:

1.4.2 decimals;

Assessment Standard 1.10: We know this when the learner uses a range of strategies to check solutions and judges the reasonableness of solutions.

Learning Outcome 2: The learner will be able to recognise, describe and represent patterns and relationships, as well as to solve problems using algebraic language and skills.

Assessment Standard 2.3: We know this when the learner represents and uses relationships between variables in a variety of ways using:

2.3.1 verbal descriptions;

2.3.3 tables.

Questions & Answers

how do I set up the problem?
Harshika Reply
what is a solution set?
Harshika
hello, I am happy to help!
Shirley Reply
please can go further on polynomials quadratic
Abdullahi
I need quadratic equation link to Alpa Beta
Abdullahi Reply
find the value of 2x=32
Felix Reply
divide by 2 on each side of the equal sign to solve for x
corri
X=16
Michael
Want to review on complex number 1.What are complex number 2.How to solve complex number problems.
Beyan
use the y -intercept and slope to sketch the graph of the equation y=6x
Only Reply
how do we prove the quadratic formular
Seidu Reply
hello, if you have a question about Algebra 2. I may be able to help. I am an Algebra 2 Teacher
Shirley Reply
thank you help me with how to prove the quadratic equation
Seidu
may God blessed u for that. Please I want u to help me in sets.
Opoku
what is math number
Tric Reply
4
Trista
x-2y+3z=-3 2x-y+z=7 -x+3y-z=6
Sidiki Reply
Need help solving this problem (2/7)^-2
Simone Reply
x+2y-z=7
Sidiki
what is the coefficient of -4×
Mehri Reply
-1
Shedrak
the operation * is x * y =x + y/ 1+(x × y) show if the operation is commutative if x × y is not equal to -1
Alfred Reply
An investment account was opened with an initial deposit of $9,600 and earns 7.4% interest, compounded continuously. How much will the account be worth after 15 years?
Kala Reply
lim x to infinity e^1-e^-1/log(1+x)
given eccentricity and a point find the equiation
Moses Reply
A soccer field is a rectangle 130 meters wide and 110 meters long. The coach asks players to run from one corner to the other corner diagonally across. What is that distance, to the nearest tenths place.
Kimberly Reply
Jeannette has $5 and $10 bills in her wallet. The number of fives is three more than six times the number of tens. Let t represent the number of tens. Write an expression for the number of fives.
August Reply
What is the expressiin for seven less than four times the number of nickels
Leonardo Reply
How do i figure this problem out.
how do you translate this in Algebraic Expressions
linda Reply
why surface tension is zero at critical temperature
Shanjida
I think if critical temperature denote high temperature then a liquid stats boils that time the water stats to evaporate so some moles of h2o to up and due to high temp the bonding break they have low density so it can be a reason
s.
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!





Source:  OpenStax, Mathematics grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11075/1.1
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Mathematics grade 7' conversation and receive update notifications?

Ask