Searching for "number"

Q:

A student multiplied a number by 3/5 instead of 5/3, What is the percentage error in the calculation ?

A) 54 % B) 64 %
C) 74 % D) 84 %
 
Answer & Explanation Answer: B) 64 %

Explanation:

Let the number be x.

Then, ideally he should have multiplied by  x by 5/3. Hence Correct result was x * (5/3)= 5x/3. 

 

By mistake he multiplied x by 3/5 . Hence the result with error  = 3x/5 

Then, error = (5x/3 - 3x/5) = 16x/15 

Error %  = (error/True vaue) * 100 = [(16/15) * x/(5/3) * x] * 100 = 64 %

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Filed Under: Percentage

Q:

The diference of two numbers is 20% of the larger number, if the smaller number is 20, then the larger number is :

A) 15 B) 25
C) 35 D) 45
 
Answer & Explanation Answer: B) 25

Explanation:

Let the large number be x.

Then x - 20 = 20x/100

=> x - x/5 = 20  => x = 25.

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Filed Under: Percentage

Q:

If 75% of a number is added to 75, then the result is the number itself. The number is :

A) 100 B) 200
C) 300 D) 400
 
Answer & Explanation Answer: C) 300

Explanation:

Let the number be x, Then 

75% of x + 75 = x 

=> x - 75x/100 =75 

=> x =  300 .

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Filed Under: Percentage

Q:

The minimum number of Non zero non collinear vectors required to produce a zero vector is

A) 3 B) 2
C) 4 D) 1
 
Answer & Explanation Answer: A) 3

Explanation:
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Filed Under: Physics

Q:

The number of members included in the Constitution Drafting Committee was

A) Seven B) Nine
C) Eleven D) Thirteen
 
Answer & Explanation Answer: A) Seven

Explanation:
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Filed Under: Indian Politics

Q:

Number of moles of CO2 present in 24 grams of carbon is

A) 0.5 B) 1
C) 2 D) 0.25
 
Answer & Explanation Answer: C) 2

Explanation:

1 mole of CO2 contain 12gms of carbon and 44 gms of CO2

therefore  24 gms of carbon is present in 88 gms of CO2 or 2 moles of CO2

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Filed Under: Chemistry

Q:

Number of moles of solute present in 1 litre of solution is

A) Normality B) Molarity
C) Molality D) Formality
 
Answer & Explanation Answer: B) Molarity

Explanation:

Moles of solute present in 1 litre or 1000ml of solution is called molarity

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Filed Under: Chemistry

Q:

The difference between a two-digit number and the number obtained by interchanging the two digits is 63. Which is the smaller of the two numbers ?

A) 12 B) 15
C) 17 D) none of these answers can be determined
 
Answer & Explanation Answer: D) none of these answers can be determined

Explanation:

Let the ten's digit be x and unit's digit be y.

Then, (10x + y) - (10y + x) = 63  

=>  9 (x - y) = 63

=> x - y = 7.

Thus, none of the numbers can be deermined..

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Filed Under: Problems on Numbers