<< Chapter < Page | Chapter >> Page > |
10.
a) Yes, area of all three figures the same
b) area = (half of base) x height
11.1 1 867 km ^{²}
11.2 530 m ^{²}
11.3 9 m by 8 m
12.
13.1
a) 3 and a quarter square cm
b) 5 square cm
13.2 A
14.1
a) 64 cm ^{²}
b) 180 cm ^{²}
c) 81 m ^{²}
d) 200 m ^{²}
14.2
a) 42 m ^{²}
b) 48 cm ^{²}
c) 65 cm ^{²}
d) 64 m ^{²}
10. BRAIN-TEASER!
A farmer divides his land as follows among his three children:
a) Was the farmer fair? __________________________ Motivate your answer:
_____________________________________________________________________
_____________________________________________________________________
b) From the above example, can you work out a formula that we use to determine the area of a triangle?
_____________________________________________________________________
11.1 Calculate the area of the farmer’s farm without the dam.
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
11.2 What is the area of this lucerne camp on the farmer’s farm?
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
11.3 The farmer wants to fence a rectangular camp with an area of 72m2. Problem: The perimeter must be kept to the minimum (because of the cost of the wire). What will the measurements of the camp be?
_____________________________________________________________________
12. A rectangular rugby field has a length of 110 m and a breadth of 60 m. What will it cost to plant grass which costs R6,45 per square metre?
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
13.1 If each square is 1 cm2, what is the area of the shaded section?
a)
_____________________________________
b)
_____________________________________
13.2 Which figure has the biggest area: A or B?
A
_____________________________________
B
_____________________________________
14. BRAINTEASERS!
14.1 Can you determine the area of the shaded parts of each figure?
a)
_____________________________________
_____________________________________
_____________________________________
b)
_____________________________________
_____________________________________
_____________________________________
c)
_____________________________________
_____________________________________
_____________________________________
d)
_____________________________________
_____________________________________
_____________________________________
14.2 Calculate the areas of the following figures?
a)
_____________________________________
_____________________________________
_____________________________________
_____________________________________
b)
_____________________________________
_____________________________________
_____________________________________
_____________________________________
c)
_____________________________________
_____________________________________
_____________________________________
_____________________________________
d)
_____________________________________
_____________________________________
_____________________________________
_____________________________________
15. CLASS DISCUSSION
15.1 Your school wants to build a new computer centre. The two possible plans that have been drawn up look like this:
A
B
a) Which plan would use the most bricks? Why?
b) Which plan would accommodate the most computers? Motivate.
c) Which plan will be the most expensive to build? Why?
15.2 A plan for a swimming pool for the school has also been drawn up:
a) What will happen to the area if the perimeter stays the same, BUT:
(i) the length increases and the breadth decreases?
(ii) the length decreases and the breadth increases?
b) When would the swimming pool have a maximum area?
Learning Outcome 4: The learner will be able to use appropriate measuring units, instruments and formulae in a variety of contexts.
Assessment Standard 4.2: We know this when the learner solves problems;
Assessment Standard 4.5: We know this when the learner calculates, by selecting and using appropriate formulae.
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 1.9: We know this when the learner uses a range of techniques to perform calculations.
Notification Switch
Would you like to follow the 'Mathematics grade 7' conversation and receive update notifications?