4
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:   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.

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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1 110
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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3 192
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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0 184
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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1 176
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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2 193
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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5 470
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

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8 325
Q:

112 × 54 =

A) 68947 B) 69874
C) 70000 D) 76000
 
Answer & Explanation Answer: C) 70000

Explanation:

112 × 54112 × 1024= 112 × 1000024= 1120000/16

= 70,000.

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10 537