Question

from a copper plate, which is a square of side 12.5 cm, a circular disc of diameter 7 cm is cut off. find the weight of the remaining part, if 1 sq cm of the plate weighs 0.8 g( assume π=22/7)? please show this step by step? please it's urgent? please

Answer 1

Given:

From a copper plate, which is a square of side 12.5 cm, a circular disc of diameter 7 cm is cut off. find the weight of the remaining part, if 1 sq cm of the plate weighs 0.8 g( assume π=22/7)?

To find:

The weight of the remaining part

Solution:

Finding the area of the square plate:

The side of the square plate = 12.5 cm

∴ The area of the square copper plate is,

= Area of a square

= side²

= 12.5²

= 156.25 cm²

Finding the area of the circular disc:

Diameter = 7 cm

So, Radius = $\frac{d}{2} = \frac{7}{2} = 3.5 \:cm$

∴ The area of the circular disc is,

= Area of a circle

= πr²

= $\frac{22}{7} \times 3.5^2$

= 38.5 cm²

Finding the area of the remaining part:

The area of the remaining part of the plate is,

= [Area of the square plate] - [Area of the circular disc]

= 156.25 cm² - 38.5 cm²

= 117.75 cm²

Finding the weight of the remaining part:

If the weight of 1 sq. cm of the plate is 0.8 g

Then,

The weight of 117.75 cm² of the plate will be,

= 0.8 g/cm² × 117.75 cm²

= 94.2 g

Thus, the weight of the remaining part of the plate is → 94.2 g.

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Also View:

a sheet 11 cm long and 2 cm wide. Circular pieces of 0.5 cm in diameter are cut from it to prepare discs, calculate the no. of discs that can be prepared.

brainly.in/question/224062

A rectangular sheet of paper is 22cm long and 6 cm wide. Circular pieces 2 cm in diameter are cut from it to prepare discs. Calculate the maximum number of discs that can be prepared. Also, find the area of the sheet left after cutting circular pieces. take pie=3.14 or 22/7

brainly.in/question/17351286

Answer 2

Answer:

94.2g

Step-by-step explanation:

Remaining area= area of square- area of circle

area of square= 12.5^2=12.5x12.5=156.25cm^2

area of circle= pie x radius^2

                        = 22/7 x 3.5 x 3.5

                        =38.5cm^2

Remaining area = 156.25-38.5= 117.75cm^2

Weight= 117.75 x 0.8

            =94.2g