Answer

Verified

438k+ views

**Hint:**In this question, we have to find the total cost of drawing a picture in this circle.

First we need to find out the area of the circle, then by unitary method we will get the total cost of drawing a picture in this circle from the given information.

**Formula used:**The area of a circle is \[\pi {r^2}\]sq. unit. Where the radius of the circle is r.

**Complete step-by-step answer:**

It is given that, in a school, exactly at the middle of the stage of the assembly hall, after drawing a circle of \[2.8\]m radius, a beautiful picture is to draw in it.

Also given that, the cost for drawing is Rs\[300\] per \[1\]sq. m.

We have the radius of the circle is r = \[2.8\]m.

We know that the area of the circle is \[\pi {r^2}\]

By substituting the value of r we get,

\[\pi {r^2} = \dfrac{{22}}{7} \times {\left( {2.8} \right)^2}\]

By cancelling the cancellable terms we get,

\[\pi {r^2} = 22 \times 2.8 \times 0.4\]

On solving we get,

\[\pi {r^2} = 24.64\]Sq. m.

Thus the area of the circle is \[\pi {r^2} = 24.64\]Sq. m.

From given we have the cost of drawing \[1\] sq. m. is Rs\[300\].

Then the cost of drawing \[24.64\] sq. m. is Rs. \[24.64 \times 300 = 7392\]

**Hence the total cost of drawing a picture in this circle is Rs. \[7392\].**

**Note:**We have solved the problem by unitary method.

Now we need to know what unitary method is.

In short, this method is used to find the value of a unit from the value of a multiple, and hence the value of a multiple.

For simplification, always write the things to be calculated on the right-hand side and things known on the left-hand side.

Using the given radius we will find the area of the circle. Here we have to find the area of the circle because while finding the area we will get the result in square units that is the total surface covered by the circle is found which will help us to find the exact value of the drawing.

Recently Updated Pages

How many sigma and pi bonds are present in HCequiv class 11 chemistry CBSE

Mark and label the given geoinformation on the outline class 11 social science CBSE

When people say No pun intended what does that mea class 8 english CBSE

Name the states which share their boundary with Indias class 9 social science CBSE

Give an account of the Northern Plains of India class 9 social science CBSE

Change the following sentences into negative and interrogative class 10 english CBSE

Trending doubts

Difference Between Plant Cell and Animal Cell

Fill the blanks with the suitable prepositions 1 The class 9 english CBSE

Which are the Top 10 Largest Countries of the World?

Give 10 examples for herbs , shrubs , climbers , creepers

Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE

How do you graph the function fx 4x class 9 maths CBSE

Differentiate between homogeneous and heterogeneous class 12 chemistry CBSE

The Equation xxx + 2 is Satisfied when x is Equal to Class 10 Maths

Change the following sentences into negative and interrogative class 10 english CBSE