Question

plz solve 4th 5th 6th sum

Answer 1

Solution:

FOR QUESTION 4:
Since the radius is 56 m.
Circumference = 2πR
= 2 × π × 56
= 351.86 m

Since the fencing is required to be done twice around the field.
Therefore, length of the wire required
= 2 × 351.86 = 703.72 m

Hence the length of the wire required to be fence around the field is 703.72 m.

.
.
.
FOR QUESTION 5:
Diameter = 84 m
Circumference = π × D
= π × 84
= 263.89 m

Since rate = ₹10.85
Therefore, cost of wire = 263.89 × 10.85
= ₹2863.21

Hence the cost of the wire to make a fence around the circular garden is ₹2863.21/-

.
.
.
FOR QUESTION 6:
Outer circumference = 660 m
& Since circumference = 2πR
Therefore, 660 = 2π × R
or R = 660/2π
or R = 105.04 m

Inner circumference = 616 m
& since circumference = 2πr
Therefore, 616 = 2πr
or r = 616/2π
or r = 98.04 m

Therefore, width of race track
= Outer Radius - Inner Radius
= 105.04 - 98.04
= 7 m

Hence the width of the race track is 7 m.