Question

find the radius of a water tank if its capacity is 3,080 m and its height is 5 m​

Answer 1

Answer:

Let the depth of the tank be h.

Given:-

Volume of tank =6160m

3

Radius of tank =14m

As we know that, volume of tank is given as-

V=πr

2

h

Therefore,

Volume of tank =πr

2

h

⇒

7

22

×(14)

2

h=6160

⇒616h=6160

⇒h=

616

6160

=10m

Hence the depth of the tank is 10m

Now again as we know that the curved surface area of cylinder is given as-

A=2πrh

Therefore,

curved surface area of tank =2×

7

22

×14×10=880m

2

Given that the cost of painting is Rs.3 per m

2

.

Therefore,

Cost of painting the curved outer surface of tank =3×880=Rs.2640

Hence the cost of painting the curved outer surface is Rs.2640.

Answer 2

Answer:

• Radius of the water tank is 14 m.

Step-by-step explanation:

Given that:

• Capacity of the water tank = 3080 m
• Height of the water tank = 5 m

To Find:

• Radius of the water tank.

As we know that:

Volume of a cylinder = (πr²h​) cubic units

Where,

• r = Radius
• h = Height

Substituting the values,

$\sf{\longrightarrow 3080=\dfrac{22}{7}\times r^2\times5}$

Transposing 22/7 and 5 to LHS and changing their sign,

$\sf{\longrightarrow \dfrac{3080\times7}{22\times5}=r^2}$

Reducing the numbers,

$\sf{\longrightarrow 28\times7=r^2}$

Multiplying the numbers,

$\sf{\longrightarrow 196 =r^2}$

Solving further,

$\sf{\longrightarrow \sqrt{196} =r}$

$\sf{\longrightarrow 14 =r}$

Hence, radius of the water tank is 14 m.

More Formulas:

• CSA of a cylinder = (2πrh) sq. units
• TSA of a cylinder = 2πr(h + r) sq. units

Abbreviations Used:

• CSA ⇢ Curved Surface Area

• TSA ⇢ Total Surface Area