Question

a square water tank has its each side equal to 40 cm there are four semi circle grassy plot all round it . find the cost of turfing plot at rs 1.25 per scam use 3.14 tick the correct options 1 12560 2 6432 3 8765 4 69 865
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Answer 1

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Given

• Side of Square tank = 40m

To Calculate

• Cost of turfing plot

Solution

According to question,

There are four semicircular grassy plot around the tank.

Diameter of the semi circular plot = 40m

Hence, radius is = 40/2 = 20m

Area of a semi circular plot

$\bf = \frac{1}{2} \pi {r}^{2}$

$\bf = \frac{1}{2} \times 3.14 \times {20}^{2}$

$\bf = \frac{1}{2} \times 3.14 \times 20 \times 20$

$\bf = 3.14 \times 10 \times 20$

$\bf = 628 {m}^{2}$

Area of four semicircular plots

= 628 × 4

= 2512m²

Cost of turfing plot at the rate of Rs. 1.25 per meter square is :-

= 2512m² × 1.25

= Rs. 3140

Therefore, cost of turfing plot is Rs.3140.

Answer 2

Answer:

Given

Side of Square tank = 40m

To Calculate

Cost of turfing plot

Solution

According to question,

There are four semicircular grassy plot around the tank.

Diameter of the semi circular plot = 40m

Hence, radius is = 40/2 = 20m

Area of a semi circular plot

\bf = \frac{1}{2} \pi {r}^{2}=21πr2

\bf = \frac{1}{2} \times 3.14 \times {20}^{2}=21×3.14×202

\bf = \frac{1}{2} \times 3.14 \times 20 \times 20=21×3.14×20×20

\bf = 3.14 \times 10 \times 20=3.14×10×20

\bf = 628 {m}^{2}=628m2

Area of four semicircular plots

= 628 × 4

= 2512m²

Cost of turfing plot at the rate of Rs. 1.25 per meter square is :-

= 2512m² × 1.25

= Rs. 3140

Therefore, cost of turfing plot is Rs.3140.