Question

5. Find the cost of putting a boundary wall around a rectangular plot 150 m long and
79 m 50 cm wide at the rate of 10 per metre. A 2 m long stretch is left on one
of the longer sides for entrance.
6. A farmer has a rectangular field of length and breadth 230 m and 170 m
respectively. He wants to fence it with barbed wire 3 times along all the 4 sides. How long barbed wire does he need?
7. A rectangular score board of a cricket playground is 25 m
50 cm long and 18 m 40 cm wide. How much electric wire
will be needed to fix all around to illuminate it?
8. Find the length of a rectangular playground whose perimeter is 400 m and breadth
is 50 m.​

Answer 1

Answer:

5./ To find :- The cost of putting boundary wall

Solution:- The length of boundary of a plot = . 150+79.5+150+79.5 = 459 metre

Now the 2 m is left therefore the length of plot for boundary wall= 459- 2 = 457 metre.

The cost of per metre = ₹10

therefore the cost of 457 metre = 457x 10 = ₹4570

6./ The total length of four sides of field = 230+ 170 +230+170

= 800metre

Now the farmer wants to fence 3 times, therefore the length will be tripled I.e. 800x 3 = 2400m

The barbed wire he needs is 2400 m

7./ Length of board = 25 m 50 cm = 25.5 m

Breadth of board = 18m 40 cm = 18.4 m

Therefore it's length is 25.5 +18.4 +25.5+18.4 = 87.8 m

Electric wire to be needed = length of board

Therefore the electric wire to be needed is 87.8 m

8./ Perimeter = 400 m

Breadth = 50 m

Length = ?

Length of playground = Perimeter - 2breadth/ 2 (because .

Perimeter = 2x length + 2x breadth )

Therefore, Length = 400- 2x50/2 =400-100 / 2 = 300/2 =150

Therefore , length of playground is 150 m

Answer 2

Answer:

pls mark as brainliest

Step-by-step explanation:

like also