###
**SBI PO, IBPS and SSC Exam, all ask questions
on quadrilaterals. Therefore it becomes only mandatory to pick up a trick or two
about solving questions on quadrilaterals.**

Questions
based on perimeter and area of quadrilaterals; find their way in most
competitive exams. However, questions on quadrilaterals can be little bit if a
challenge if you don’t remember the formulas to calculate the area and
perimeter. But relax we have you covered!

So in our
exclusive series of blog posts about smart methods that help you solve
questions in 5- 10 seconds, the 8

^{th}Smart Method is about questions on Quadrilaterals. We promise you that if you use this method to solve questions about area of quadrilateral, it won’t take you more than 10 seconds!###
**Area of Quadrilaterals **

A
quadrilateral is a closed four sided figure having two dimensions. Some common
quadrilaterals are- Square, Rectangle, Parallelogram, Rhombus and Trapezium. As
students most of us study the different kinds of quadrilaterals during high
school and cram their properties and formulas to be able to solve questions on
Quadrilaterals.

###

**Formulas for Area of Quadrilaterals**

###
**Example of a Question on Area of
Quadrilaterals**

The
length of a rectangle is increased by 40% and its breadth increased by 20%. What will be the percentage increase in the
area of the rectangle?

1) 50% 2)10% 3) 44% 4) 68% 5) None of these

###
** ****Conventional Method to Solve
Questions on Quadrilaterals**

On reading
the above question most of us would quickly assume values for the length and
breadth of the rectangle, then increase then by the given values, apply the
formula for the area of the quadrilateral, calculate the new area and then find
the change based on the given values. Let’s see the steps involved-

Assuming the
Length and Breadth of the rectangle to be L an B respectively,

**Step 1:**

Area of the
rectangle= L x B= LB

**Step 2:**

New length
of the rectangle= L+ 40%= 1.4L

**Step 3:**

New breadth
of the rectangle= B+ 20%= 1.2B

**Step 4:**

New area of
the rectangle= 1.4L x 1.2B= 1.68

**Step 5:**

Percentage
of increase in the area= {(New Area- Old Area)/ Old Area}X 100

**Step 6:**

{(1.68LB-
LB)/LB} x100= .68x 100= 68%

Phew! Trust
me that was a lot of calculation of a problem as simple as that.

###
**Smart Method to Solve Questions on
Area of Quadrilaterals **

Let’s
discuss how we can reduce these 40 seconds to 15 seconds or even less by using
the

*concept of effective percentage, the formula for which is = A+ B+ (AxB)/100.*
Assuming change
in length and breadth to be A and B respectively, A= 40, B= 20

**Step 1:**

Percentage change
in area= 40+ 20 + (40x 20)/100= 60+ (800/100)= 68%

Wasn’t that
quick and simple!

Time to try
some questions using the time saving smart method you just learnt!

Question 1: The length of a rectangle is increased by 20% and its breadth
increased by 10%.

What
will be the percentage increase in the area of the rectangle?

1)23%
2)25% 3)
32% 4) 30% 5) None of these

Question 2: The length of a rectangle is increased by 50% and its breadth
decreased by 20%. What will be the percentage increase in the area of the
rectangle?

1) 10% 2)20%
3) 30% 4) 40% 5) None of these

Do write
your answers in the comment section and tell us how you liked this smart method
to solve questions on quadrilaterals.

Keep
watching this space for more smart methods and keep practicing using smart methods.

1)32%. 2)20%

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