To calculate through selection and by using suitable computations [lo 1.8.3]
To describe observed relationships and rules in your own words [lo 2.2]
1. Look carefully at the following problems and explain to a friend what your approach would be in calculating the various answers.
1.1
1.2
1.3
1.4
1.5
1.6
Now calculate the answers.
2. Check your answers with your friend.
Activity 2:
To calculate through selection and by using suitable computations [lo 1.8.6]
To determine, through comparison and discussion, the equivalence and validity of different representations of the same problem [lo 2.6.2]
To describe observed relationships and rules in your own words [lo 2.2]
Sometimes one can use a pie graph to represent fractions. A survey was done of the extramural activities of a Grade 5 class and the results were represented by using a pie graph. See whether you can “read” it, and then complete the table.
Activity
Netball
Tennis
Rugby
Choir
Chess
Swimming
Fraction
...........
...........
...........
...........
...........
...........
2. It is important for us to be able to interpret the pie graph, otherwise we will not be able to make meaningful deductions from it and solve the problems. Work through the following problem with a friend and find out how many methods can be used to solve it.
If there are 50 learners in the class, how many learners play netball?
2.1 The question is
of 50
of 50 = 5
of 50 will be 15
2.2 I must calculate
of 50. I find out what
is by dividing 50 by 10.
50 ÷ 10 = 5
If one tenth is 5, then 3 tenths will be 3 × 5. There are thus 15 pupils who play netball.
2.3 Girls =
of 50
Thus: = (50 ÷ 10) × 3
= 5 × 3
= 15
2.4
of 50 = 3 ×
of 50
= 3 × 5
= 15
3. What would you say is the “rule” for these “of” sums?
4. Which of these methods do you prefer?
Why?
5. Look again at the methods at 2.1 and 2.2. What do you notice?
6. Can you say how many learners in Act. 2 participate in:
rugby?_______ ; swimming? _________
7 Now calculate:
7.1
of 36
7.2
of 32
7.3
of 350
7.4
of 224
Do you still remember?
1 000 m. = 1 litre
1 000 litre = 1 kℓ
1 000 g = 1 kg
1 000 kg = 1 t
1 000 mm = 1 m
1 000 m = 1 km
Activity 3:
To calculate through selection and by using suitable computations [lo 1.8.6]
1. Let us see whether you are able to successfully apply the knowledge that you have acquired up to now. Work on your own and calculate:
1.1 Five learners share 1 litre of cool drink equally. How many m
does each learner get?
1.2 Zane lives 2 km from the school. He has already covered
of the distance. How far has he walked? (Give your answer in m).
1.3 The mass of a bag of flour is 1 kg. Mom needs
of this to bake a cake. How much flour will she use?
1.4 Joy buys 3 m of material but only uses
of this to make a dress.
What fraction of material is left over?
How much material is left over?
Activity 4:
To use tables and graphs to arrange and record data [LO 5.3]
Wayne and Dennis like to ride the bike path from Riverside Park to the beach. Dennis’s speed is seven miles per hour faster than Wayne’s speed, so it takes Wayne 2 hours to ride to the beach while it takes Dennis 1.5 hours for the ride. Find the speed of both bikers.
from theory: distance [miles] = speed [mph] × time [hours]
info #1
speed_Dennis × 1.5 = speed_Wayne × 2
=> speed_Wayne = 0.75 × speed_Dennis (i)
info #2
speed_Dennis = speed_Wayne + 7 [mph] (ii)
use (i) in (ii) => [...]
speed_Dennis = 28 mph
speed_Wayne = 21 mph
George
Let W be Wayne's speed in miles per hour and D be Dennis's speed in miles per hour. We know that W + 7 = D and W * 2 = D * 1.5.
Substituting the first equation into the second:
W * 2 = (W + 7) * 1.5
W * 2 = W * 1.5 + 7 * 1.5
0.5 * W = 7 * 1.5
W = 7 * 3 or 21
W is 21
D = W + 7
D = 21 + 7
D = 28
Salma
Devon is 32 32 years older than his son, Milan. The sum of both their ages is 54 54. Using the variables d d and m m to represent the ages of Devon and Milan, respectively, write a system of equations to describe this situation. Enter the equations below, separated by a comma.
please why is it that the 0is in the place of ten thousand
Grace
Send the example to me here and let me see
Stephen
A meditation garden is in the shape of a right triangle, with one leg 7 feet. The length of the hypotenuse is one more than the length of one of the other legs. Find the lengths of the hypotenuse and the other leg
however, may I ask you some questions about Algarba?
Amoon
hi
Enock
what the last part of the problem mean?
Roger
The Jones family took a 15 mile canoe ride down the Indian River in three hours. After lunch, the return trip back up the river took five hours. Find the rate, in mph, of the canoe in still water and the rate of the current.
Shakir works at a computer store. His weekly pay will be either a fixed amount, $925, or $500 plus 12% of his total sales. How much should his total sales be for his variable pay option to exceed the fixed amount of $925.
I'm guessing, but it's somewhere around $4335.00 I think
Lewis
12% of sales will need to exceed 925 - 500, or 425 to exceed fixed amount option. What amount of sales does that equal? 425 ÷ (12÷100) = 3541.67. So the answer is sales greater than 3541.67.
Check:
Sales = 3542
Commission 12%=425.04
Pay = 500 + 425.04 = 925.04.
925.04 > 925.00
Munster
difference between rational and irrational numbers
Jazmine trained for 3 hours on Saturday. She ran 8 miles and then biked 24 miles. Her biking speed is 4 mph faster than her running speed. What is her running speed?