3
Q:

Find by how much percentage the average of first 10 odd numbers (starting from 1) is greater than the last term ?

A) 991/16 % B) 900/19 %
C) 874/13 % D) 719/17 %

Answer:   B) 900/19 %



Explanation:

First ten odd numbers form an arithmetic progression of the form
1,3,5,7,9......
here a = first term = 1
d = common difference = 2
Average of first n numbers = (2a + (n - 1)d)/2
n th term of the AP = a + (n - 1)d
Substituting a = 1, d = 2 and n = 10 in the above formulas
average of first 10 numbers = 10
10 th term of the AP = 19
Therefore average of first 10 terms is 19 - 10 = 9 greater than
the last term. Hence the average is greater than the sum by
9/19 X 100 = 900/19 %

Q:

How many inches is 5' 4"?

A) 66 B) 64
C) 62 D) 60
 
Answer & Explanation Answer: B) 64

Explanation:

We know 1 feet = 12 inches.

According to the question,

5' 4''  =  5 feet 4 inches = 12 x 5 + 4 = 64 inches.

 

Hence,  5' 4''  =  5 feet 4 inches = 64 inches. 

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0 51
Q:

Multiplicative inverse of 0

A) 0 B) 1
C) infinity D) None of the above
 
Answer & Explanation Answer: D) None of the above

Explanation:

In the real numbers, zero does not have a reciprocal because no real number multiplied by 0 produces 1 (the product of any number with zero is zero).

 

Hence, 0 doesn't have any multiplicative inverse.

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0 102
Q:

6 divided by 2(1 + 2) =

A) 1 B) 0
C) 9 D) Can't be determined
 
Answer & Explanation Answer: C) 9

Explanation:

The given expression can be simplified as

÷ 2 (1 + 2)

The expression can be simplified further by the order of operations, using BODMAS rule.

 

First evaluate Parentheses/Brackets, then evaluate Exponents/Orders, then evaluate Multiplication-Division, and finally evaluate Addition-Subtraction.

 

Now, the expression becomes ÷ 2 (3)

 

According to the order of operations, division and multiplication have the same precedence, so the correct order is to evaluate from left to right. First take 6 and divide it by 2, and then multiply by 3.

6 ÷ 2 × 3

= 3 × 3

= 9

But not  6÷2×3 = 6 ÷ 6 = 1

Screenshot_(21)1528090844.jpg image 

 

Hence, 6 ÷ 2 (1 + 2) = 9.

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0 117
Q:

Multiplicative inverse of 7?

A) 1 B) -1/7
C) 0 D) 1/7
 
Answer & Explanation Answer: D) 1/7

Explanation:

Multiplicative inverse is nothing but a reciprocal of a number. 

It is defined as one of a pair of numbers that when multiplied with another number equals the number 1.

Multiplicative inverse or reciprocal of 7 is 

7 x n = 1

=> n = 1/7.

 

Hence, Multiplicative inverse or reciprocal of 7 is  1/7.

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2 98
Q:

What is the product of a number and its reciprocal?

A) 0 B) 1
C) -ve of the number D) the number itself
 
Answer & Explanation Answer: B) 1

Explanation:

The product of a number and its reciprocal is always equals to 1.

 

For Example : Let the number be 4.

Now, its reciprocal is 1/4

Hence, required product = 4 x 1/4 = 1.

 

Now, take the number as -15.

Then its reciprocal is -1/15

Required product = -15 x -1/15 = 1.

 

Hence, the product of a number and its reciprocal is 1.

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0 134
Q:

A plane is an undefined term because it

A) is a flat surface that extends indefinitely in all directions B) is where other geometric shapes can be constructed
C) is described generally, not using a formal definition D) can be named using three noncollinear points
 
Answer & Explanation Answer: C) is described generally, not using a formal definition

Explanation:

In geometry, we can define plane as a flat surface with no thickness.

The surface extends with no ends.

A plane does not have any edges even if we draw it on paper with edges, it does't mean it has edges.

 

Hence, A plane is an undefined term because it is described generally, not using a formal definition.

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0 177
Q:

Absolute value of 9?

A) 0 B) 9
C) 8 D) -9
 
Answer & Explanation Answer: B) 9

Explanation:

Absolute value of a number :

It means that the distance of a number from 0 on a number line. 

 

Here absolute value of 9 is that on a number line 9 is 9 units away from 0. Hence its absolute value is 9. Similarly, absolute value of -9 means -9 is also 9 units away from the 0 on number line. Hence, absolute value of -9 is also 9.

 

Hence, the absolute value of 9 is 9.

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1 225
Q:

What is the value of 62 tens?

A) 6 B) 620
C) 62 D) 2
 
Answer & Explanation Answer: B) 620

Explanation:

Here in the question it is asked that 62 tens, which implies ten times of 62.

=> 62 x 10 = 620.

 

Hence, the value of 62 tens = 620.

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3 229