Question

Tublu buys a cylindrical water tank of height 1.4m and diameter 1.1m to catch rainwater off his roof. He has a full 2 litres tin of paint in his store and decides to paint the tank (not the base). If he uses 250 ml to cover 1 , will he have enough paint to cover the tank with one layer of paint? [take π=3.142]

Answer 1

Answer:

Yes, he will have enough paint to cover the tank with one layer of paint.

Step-by-step explanation:

We are given that Tublu buys a cylindrical water tank of height 1.4 m and diameter 1.1 m to catch rainwater off his roof. He has a full 2 liters tin of paint in his store and decides to paint the tank (not the base).

He uses 250 ml to cover 1 $\text{m}^{2}$.

From the question, it is clear the area of the tank which needs to be painted is the lateral surface area (because the base is not included).

The lateral surface area of the cylinder = $2\pi rh$

where, r = radius of the cylinder =  $\frac{\text{Diameter}}{2}$  = $\frac{1.1 }{2}$ = 0.55 m

           h = height of the cylinder = 1.4 m

           $\pi$ = 3.142 (given)

So, the lateral surface area of a cylindrical water tank = $2 \times 3.142 \times 0.55 \times 1.4$

                                                                                         = 4.84 $\text{m}^{2}$.

Now, it is given in the question that; Tublu uses 250 ml to cover 1 $\text{m}^{2}$ area, this means that;

To cover 4.84 $\text{m}^{2}$ area, he will use paint = $4.84 \times 250$ = 1210 ml

Since he has a full 2 liters tin of paint in his store which is equal to 2000 ml but he need only 1210 ml of paint.

This means that yes, he will have enough paint to cover the tank with one layer of paint.