Question

In a field, the length is 45m and breadth is 4000cm, then find the cost of tilling the field at the rate of Rs 12 per sq m.
Rs. 21600
Rs. 31600
Rs. 21100
Rs. 20000

Answer 1

Hint: First, convert the breadth from cm to m. Then find the area of the field by multiplying the length and breadth of the field. As the cost of tilling is Rs. 12 per sq m. Then multiply the area by 12 to get the cost of tilling of the field.

Complete step by step answer:
Given: - Length of the field is 45m
The breadth of the field is 4000 cm
The cost of tilling per sq m is Rs 12.
Now, change the breadth from centimeter to meter,
As we know that $1cm = \dfrac{1}{{100}}$ m. Then, the breath of the field in the meter is,
$ \Rightarrow b = \dfrac{{4000}}{{100}}$m
Divide numerator by denominator on the right side,
$ \Rightarrow b = 40$m
Now, find the area of the field by multiplying the length and breadth of the field,
$ \Rightarrow A = l \times b$
Substitute the values,
$ \Rightarrow A = 45 \times 40$
Multiply the terms on the right side,
$ \Rightarrow A = 1800{m^2}$
As we know that the cost of tilling is Rs 12 per sq m. Then,
$ \Rightarrow $ Cost of tilling = Area of the field $ \times $ Cost of tilling per sq m
Substitute the values,
$ \Rightarrow $ Cost of tilling $ = 1800 \times 12$
Multiply the terms on the right side,
$ \Rightarrow $ Cost of tilling $ = 21600$
Thus, the cost of tilling on the field is Rs 21600.

Hence, option (A) is the correct answer.

Note: The students are likely to make mistakes in questions which have units in a different form. Students are advised to use common conversions first to convert all the values in the same unit and then do calculations.
Rectangle: A rectangle is a quadrilateral with four sides. The opposite side of a rectangle is parallel to each other. The opposite faces of the rectangle are of equal measure. A rectangle has four angles, each measuring about 90 degrees. As like a square, a rectangle is also called an equiangular quadrilateral.