4
Q:

A man could buy a certain number of notebooks for Rs.300. If each notebook cost is Rs.5 more, he could have bought 10 notebooks less for the same amount. Find the price of each notebook ?

A) 15 B) 20
C) 10 D) 8

Answer:   C) 10



Explanation:

Let the price of each note book be Rs.x.

Let the number of note books which can be brought for Rs.300 each at a price of Rs.x be y.

Hence xy = 300

=> y = 300/x

(x + 5)(y - 10) = 300 => xy + 5y - 10x - 50 = xy

=>5(300/x) - 10x - 50 = 0 => -150+x2+5x

multiplying both sides by -1/10x

=> x2+15x-10x-150=0

=> x(x + 15) - 10(x + 15) = 0

=> x = 10 or -15

As x>0, x = 10.

Q:

5 + 2 x 10 =

A) 70 B) 20
C) 25 D) 52
 
Answer & Explanation Answer: C) 25

Explanation:

According to BODMAS rule,

After multiplication only, addition is done.

Hence,

5 + 2 x 10 = 5 + 20 = 25.

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1 38
Q:

Simplify

39.96% of 649.85 ÷13.07 = 45.14 - ?

A) 25 B) 26
C) 27 D) 28
 
Answer & Explanation Answer: A) 25

Explanation:

This can be easily simplified by Approximation process

Given 39.96% of 649.85 ÷13.07 = 45.14 - ? can be written as 

40% of 650 ÷13 = 45 - ?

 

40 x 65010013 = 45 - ?? = 45 - 20? = 25.

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0 323
Q:

Simplify the fraction?

5 (2/7) - 3 (1/14) - 2 (1/14) - 1 (1/7) = ? + 3 (1/17) 

A) -4 (1/17) B) 5 (2/17)
C) -2 (1/17) D) 3 (3/17)
 
Answer & Explanation Answer: A) -4 (1/17)

Explanation:

Given fraction is 5 (2/7) - 3 (1/14) - 2 (1/14) - 1 (1/7) = ? + 3 (1/17) 

It can be written as 

(5 - 3 - 2 - 1) + (2/7 - 1/14 - 1/14 - 1/7) = ? +  3 (1/17) 

-1 + 0 - 3 (1/17) = ?

=> ? = -4 (1/17)

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2 350
Q:

5 + 2 x 10/2 = ?

A) 15 B) 35
C) 10 D) 20
 
Answer & Explanation Answer: A) 15

Explanation:

Using BODMAS Rule,

First solve division, mutiplication and Addition

So here 10/2 = 5

Then 2 x 5 =  10

Now, 5 + 10 = 15.

 

Hence, 5 + 2 x 10/2 = 15.

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4 512
Q:

Simplify the following :

4 15 × 3 13 + ? = 20% of 120

A) 10 B) 24
C) 36 D) 40
 
Answer & Explanation Answer: A) 10

Explanation:

Given equation can be written as

215 x 103 + ? = 24=> 14 + ? = 24=> ? = 24 - 14=> ? = 10

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0 424
Q:

Simplify the following expression?

40% of (244 x ?) = 48

A) 24 B) 22
C) 20 D) 18
 
Answer & Explanation Answer: C) 20

Explanation:

We know that 

40% = 40100 = 2525 x 244 x ? = 48? = 48 x 5 x 42 x 24 = 20

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1 422
Q:

Derivative of sinx by first principle?

A) -sinx B) -cosx
C) cosx D) sinx
 
Answer & Explanation Answer: C) cosx

Explanation:

Screenshot_(1)1519127168.png image

 

Thus, the derivative of sinx by first principle is cosx.

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2 440
Q:

Simplify the following and find the value of ?

 

13 of ? + 47 of 114 of 539 = 31% of 2000

A) 1134 B) 1237
C) 1187 D) 1249
 
Answer & Explanation Answer: A) 1134

Explanation:

13 x ? + 47 x 114 x 539 = 31100 x 2000? = 378 x 3? = 1134

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5 1151