Question

Crack it!
(1) The total cost of fencing a rectangular field at the rate of 31/mis 2914. If its length
is 25 m, find its breadth. (Hint: First divide the total cost by rate to find the perimeter.)
(2) The length and breadth of a rectangle are in the ratio 3:2. If its perimeter is 3 m
80 cm, find its dimensions. (Hint: Convert perimeter to cm and find one part by division:
then multiply by number of parts.)
(3) Seven square flower beds each of side 2 m are dug on a piece of land 8 m long and
5 m wide. What is the area of the remaining part of the land?
(Hint Find the total area of 7 flower beds by multiplication, and then subtract.)
(4) The length of a rectangular stadium is twice its breadth. Varun ran around it 6 times
and covered a distance of 3.6 km. What is the length of the field?
(Hint Let the breadth be x and length be 2x; write an expression for perimeter and
equate it to distance of one round.)
(5) Johnson wants to buy a new carpet for his living room. If the dimensions of his
living room are 650 cm x 320 cm, calculate in sq.m, the area that will be covered
by the carpet. (Hint: Convert the dimensions to metre and multiply.)​

Answer 1

1. rate of fencing = 31/m

total rate= perimeter × rate of fencing

2914=perimeter×31

perimeter=94 m

perimeter =2(l+b)

94=2(25+b)

47=25+b

b= 22 m

2.perimeter = 3.80m

perimeter =2(l+b)

3.80=2(3x+2x)

1.90=5x

x=0.38

length=3×0.38=1.14m

breadth=2×0.38=0.76m

3.area covered by one flower bed=2×2=4m²

area covered by 7 flower bed=7×4m²=28m²

area of land= 8×5=40m²

area of remaining land=40-28=12m²