Simplification Questions

FACTS  AND  FORMULAE  FOR  SIMPLIFICATION  QUESTIONS

 

 

1. BODMAS Rule: This rule depicts the correct sequence in which the operations are to be executed,so as to find out the value of a given expression. Here, 'B' stands for bracket , 'O' for of , 'D' for division and 'M' for multiplication, 'A' for addition and 'S' for subtraction.

Thus, in simplifying an expression, first of all the brackets must be removed, strictly in the order(), {} and [].

After removing the brackets, we must use the following operations strictly in the order:

(1) of    (2)division   (3) multiplication   (4)addition   (5)subtraction.

 Modulus of a real number : Modulus of a real number a is defined as |a| = aif a>0-aif a<0

 

2. Virnaculum (or bar) : When an expression contains Virnaculum, before applying the ‘BODMAS’ rule, we simplify the expression under the Virnaculum.

Q:

Two parallel chords on the same side of the centre of a circle are 5 cm apart. If the chords are 20 and 28 cm long, what is the radius of the circle? 

A) 14.69 cm B) 15.69 cm
C) 18.65 cm D) 16.42 cm
 
Answer & Explanation Answer: B) 15.69 cm

Explanation:

circle11487663359.jpg image

Draw the two chords as shown in the figure. Let O be the center of the circle. Draw OC
perpendicular to both chords. That divides the two chords in half.
So CD = 10 and AB = 14. Draw radii OA and OD, both equal to radius r.
We are given that BC = 5, the distance between the two chords. Let
OB = x.

We use the Pythagorean theorem on right triangle ABO

AO² = AB² + OB²
r² = 14² + x²

We use the Pythagorean theorem on right triangle DCO

DO² = CD² + OC²

We see that OC = OB+BC = x+5, so

r² = 10² + (x+5)²

So we have a system of two equations:

r² = 14² + x²
r² = 10² + (x+5)²

Since both left sides equal r², set the right sides
equal to each other.

14² + x² = 10² + (x+5)²
196 + x² = 100 + x² + 10x + 25
196 = 125 + 10x
71 = 10x
7.1 = x

r² = 14² + x²
r² = 196 + (7.1)²
r² = 196 + 50.41
r² = 246.41
r = √246.41
r = 15.69745202 cm

Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: AIEEE , Bank Exams , CAT , GATE
Job Role: Bank Clerk , Bank PO

4 4029
Q:

Simplify: b-[b-(a+b)-{b-(b-a-b)}+2a]

A) 2b B) 1
C) 0 D) 3b
 
Answer & Explanation Answer: C) 0

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: Bank Exams

14 3912
Q:

An owner of a Dry fruits shop sold small packets of mixed nuts for Rs. 150 each and large packets for Rs. 250 each. One day he sold 5000 packets, for a total of Rs. 10.50 lakh. How many small packets were sold ?

A) 2000 B) 3000
C) 2500 D) 3500
 
Answer & Explanation Answer: A) 2000

Explanation:

Let 's' be the number of small packets and 'b' the number of large packets sold on that day.

 

Therefore, s + b = 5000 ... eqn (1)

 

Each small packet was sold for Rs.150.
Therefore, 's' small packets would have fetched Rs.150s.

 

Each large packets was sold for Rs.250.
Therefore, 'b' large packets would have fetched Rs.250b.

 

Total value of sale = 150s + 250b = Rs. 10.5 Lakhs (Given)

 

Or 150s + 250b = 10,50,000 ... eqn (2)

 

Multiplying equation (1) by 150, we get 150s + 150b = 7,50,000 ... eqn (3)

 

Subtracting eqn (3) from eqn (2), we get 100b = 3,00,000
Or b = 3000

 

We know that s + b = 5000
So, s = 5000 - b = 5000 - 3000 = 2000.

 

2000 small packets were sold.

Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: GATE , CAT , Bank Exams , AIEEE
Job Role: Bank PO , Bank Clerk

7 3686
Q:

A class consists of both boys and girls along with a teacher. After a class, the teacher drinks 9 litres of water, a boy drinks 7 litres of water and a girl drinks 4 litres of water. If after a class 42 litres of water was consumed, find the number of girls in the class ?

A) 8 B) 6
C) 5 D) 3
 
Answer & Explanation Answer: D) 3

Explanation:

Given teacher drinks 9 ltr
Let number of boys be 'A'.
Let number of girls be 'B'.
Boy drinks 7 ltr and girl drinks 4 ltr
After class total water consumed = 42 ltr
Then,
9 + 7A + 4B = 42
=> 7A + 4B = 33
By trial and error method,
The only integers which satisfy the equation is A = 3 and B = 3
Therefore, number of girls in the class = 3.

Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: AIEEE , Bank Exams , CAT , GATE , GRE
Job Role: Analyst , Bank Clerk , Bank PO

6 3617
Q:

In a party there are male and female members. If 15 female quit then the number of females will become double the number of males. If 45 males quit no. of female becomes five times the number of males. Find the number of females ?

A) 175 B) 145
C) 165 D) 135
 
Answer & Explanation Answer: A) 175

Explanation:

Let the number of males be 'M'
Let the number of females be 'F'
From the given conditions,
(F-15)=2M.....(i)
F=5(M-45).....(ii)
By solving the equations (1) & (2) we get M = 80
Then substitute M = 80 in (1)
F = 2M + 15
F = 2 x 80 + 15
=> F = 175
Therefore, number of males = 80 and females = 175 in the party.

Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: AIEEE , Bank Exams , CAT , GATE , GRE
Job Role: Bank Clerk , Bank PO

5 3452
Q:

What is the value of sin 46 cos 44+ cos 46 sin 44?

A) 2 B) sin 2
C) 1 D) 0
 
Answer & Explanation Answer: C) 1

Explanation:

sin 46. cos 44+ cos 46. sin 44

sin 46. sin (90 -44)+ cos 46. cos (90 -44)

= sin^2 46 + cos^2 46

= 1

Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: Bank Exams

3 3386
Q:

If (4a +7b) (4c-7d) = (4a -7b) (4c +7d, then which one of the following is correct ?

A) a/b = c/d B) a/d = c/b
C) a/b = d/c D) none
 
Answer & Explanation Answer: A) a/b = c/d

Explanation:

(4a+7b)(4c-7d) = (4a-7b)(4c+7d)

(4a+7b)/(4a-7b) = (4c+7d)/(4c-7d)

Using componendo and dividendo

(4a+7b)+(4a-7b) / (4a+7b)-(4a-7b)

= (4c+7d)+(4c-7d) / (4c+7d)-(4c-7d)

Or 8a/14b = 8c/14d

Or a/b = c/d

Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: Bank Exams

3 3333
Q:

Simplify  413 + 215 + 414 = ?

A) 10 47/60 B) 11 45/73
C) 11 47/36 D) 10 35/48
 
Answer & Explanation Answer: A) 10 47/60

Explanation:

The given equation is in Mixed fraction.

Now to solve this type of fractions,

413 + 215 + 414 =?? = 4 + 2 + 4 + 13 + 15 + 14 ? = 10 + 4760? = 104760

Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: AIEEE , Bank Exams , CAT , GATE
Job Role: Analyst , Bank Clerk , Bank PO

9 3294