Tag: perimeter and area of rectilinear figures

The cubic unit is used to measure volume.

All volumes are measured in cubic units, as it is the space occupied in all the three dimensions. So, when we talk about volume, actually we talk about length, width and height of the solid.

Yes the region covered by the enclosed figure or the total surface covered is the area of the particular shape.True.Option A

The measurement of area is done in square units.

Length of the boundary is the Perimeter not the area. The region enclosed inside the boundary is the area.
Therefore the statement is false.
Option B

Volume is measured in cubic units.

According to given question,

 Two ppes can fill atank $=20\,and\ 24\,\min .$

A waste pipe can empty$=3\,gallon/\min .$

Three pipes working$=15\,\min .$

So, According to given question,

Work done by the waste pipe in 1 minute

$ =\dfrac{1}{15}-\left( \dfrac{1}{20}+\dfrac{1}{24} \right) $

$ =\dfrac{1}{15}-\dfrac{11}{120} $

$ =-\dfrac{1}{40} $

Note:- negative sign means emptying

Then,

Volume of $\dfrac{1}{40}\,part$ $=\,3\,gallons.$

Volume of whole$=3\times 40=120\,gallons.$

Hence, this is the answer.

The area of a flat, or plane figure is the number of unit squares that can be contained within it.

The amount of surface enclosed by a closed plane figure is called its area.

Let the length and breadth be 2x and 3x respectively. Then, floor area $= 6x^2$ sq.m. 
Cost of flooring at the rate of Rs. 4.00 per $m^2 = $ Rs. 216
$\therefore 6x^2 \times 4 = 216$
or $x^2 = 9$
or $x = 3$
$\therefore $ Length = 3x = 9m
Breadth = 2x = 6m
and Height $= \displaystyle \frac{1}{2} \times$ Length = 4.5 m
$\therefore $ Area of four walls = 2(length $\times$ height + breadth $\times$ height)
$=2 [9 \times 4.5 + 6 \times 4.5] = 135 m^2$