Area And Perimeter(7th Grade > Mathematics ) Questions and answers for exam Preparation

7th Grade > Mathematics

AREA AND PERIMETER MCQs

Perimeter And Area

Total Questions : 99 | Page 4 of 10 pages

Question 31. There is a square park in a society of side 7 m. What is the cost of laying bricks in the park at the rate of ₹ 10 / m².

₹470
₹440
₹490
₹500

Discuss Question

Answer: Option C. -> ₹490
:
C
Total cost of laying bricks in the park= Area of the park x rate
Area of a the park= (7x 7) m²
= 49m²
Cost = 49m² x ( ₹ 10) / m²
= ₹ 490

Question 32. What is the radius (in cm) of the tyre in a car, if it covers 0.396 km in 300 rotations? (Use π =

\frac{22}{7}

)

14 cm
21 cm
7 cm
28 cm

Discuss Question

Answer: Option B. -> 21 cm
:
B
The circumference of the tyre = 2πr (Distance travelled in each rotation)
Total Distance = Distance covered in 1 rotationx Number of rotations

\Rightarrow 0.396 = 2 \times \frac{22}{7} \times r \times 300

\Rightarrow r = \frac{0.396 \times 7}{2 \times 22 \times 300}

Hence r =0.00021km or 21cm.

Question 33. Calculate the area of a rectangle whose length and breadth are 12 cm and 8 cm respectively.

96 cm2
192 cm2
196 cm2
48 cm2

Discuss Question

Answer: Option A. -> 96 cm2
:
A
The area A of a rectangle is given by:

A = l e n g t h \times b r e a d t h

Therefore, for the given rectangle , we have

A = 12 \times 8 = 96 c m^{2}

Question 34. Statement 1: The area of a quarter circle is one-fourth of that of a circle with same radius.
Statement 2: The circumference of a quarter circle is one-fourth of that of a circle with same radius.

Both the statements are true
Statement 1 is true and statement 2 is false
Statement 1 is false and statement 2 is true
Both the statements are false

Discuss Question

Answer: Option B. -> Statement 1 is true and statement 2 is false
:
B
The area of a quarter circle is one-fourth of that of the complete circle because the area is the region enclosed. For a semi-circle, it is half of the total area and for quarter circle, it is one-fourth. So, area of a quarter circle with radius

r = \frac{π r^{2}}{4}

The circumference is the length of the boundary. For a quarter circle with radius r, circumference is given by

(\frac{π r}{2}) + 2 r

.
So, statement 1 is true and statement 2 is false.

Question 35. One fine morning, Ted woke up and found his dad gardening. His dad was planning to fence the garden with plants. How many saplings should he buy so that his dad can fence the garden with 5 plants every 2.5 metres?

Discuss Question

Answer: Option D. -> 82
:
D
For 2.5 m, number of saplings required = 5
For 1 m, number of saplings required =

\frac{5}{2.5}

= 2
Ted has to plant 2 plants per metre.
Perimeter of the garden = (10.2 + 11.4 + 10.6 + 8.8) m = 41.0 m = 41 m
For 1 m, Ted needs 2 plants.
So, for 41 m, Ted is going to need = 41

\times

2 = 82 saplings.

Question 36. If the edge length of a square is

a

units, the area of the square is

\frac{a^{2}}{2}

square units.

True
False
12 cm2
14 cm2

Discuss Question

Answer: Option B. -> False
:
B
The area of a square is given by squaring its edge length. So the area of the given square is

a^{2}

Question 37. In order to plant 4 plants per meter, how many plants should you buy to edge your garden along the path as in the given figure?

Discuss Question

Answer: Option D. -> 30
:
D
You can plant 4 plants per meter.
The perimeter of the garden = 1.25m + 3m + .75m + 2.5m = 7.5m
If in 1m4 plants can be planted, then in7.5m,7.5 × 4 = 30 plants can be planted.
So, 30 plants need to be bought.

Question 38. The perimeter of a circle with a diameter = '14 cm' is equal to 88 cm.