Which number will come in place of question mark 7, 16, 36, 78, 144, ?

Correct Answer: 8 and 5

Explanation:

Let the number  be 476ab0 

 

476ab0 is divisible by 3 

=> 4 + 7 + 6 + a + b + 0 is divisible by 3

=> 17 + a + b is divisible by 3 ------------------------(i)

 

476ab0 is divisible by 11

[(4 + 6 + b) -(7 + a + 0)] is 0 or divisible by 11

=> [3 + (b - a)] is 0 or divisible by 11  --------------(ii)

 

Substitute the values of a and b with the values given in the choices and select the values which satisfies both Equation 1 and Equation 2.

 

if a=6 and b=2, 

17 + a + b = 17 + 6 + 2 = 25 which is not divisible by 3 --- Does not meet equation(i).Hence this is not the answer

 

if a=8 and b=2, 

17 + a + b = 17 + 8 + 2 = 27 which is divisible by 3 --- Meet equation(i)

[3 + (b - a)] = [3 + (2 - 8)] = -3 which is neither 0 nor divisible by 11---Does not meet equation(ii).Hence this is not the answer

 

if a=6 and b=5, 

17 + a + b = 17 + 6 + 5 = 28 which is not divisible by 3 --- Does not meet equation (i) .Hence this is not the answer

 

 

if a=8 and b=5, 

17 + a + b = 17 + 8 + 5 = 30 which is divisible by 3 --- Meet equation 1

[3 + (b - a)] = [3 + (5 - 8)] = 0 ---Meet equation 2

Since these values satisfies both equation 1 and equation 2, this is the answer

Correct Answer: 4964

Explanation:

The pattern is  1 2 2 2 , 3 2 4 2 , 5 2 6 2, 

?The next number= 7 2 8 2= 4964

Correct Answer: 100

Explanation:

Let the number be x.Then

 

60% of 3 5of x=36.

 

=>  60 100 * 3 5 * x = 36

 

=>  9 x 25 = 36 => x= 25 * 36 9 = 100

 

Required number is 100.

Correct Answer: ⁴⁄₅

Explanation:

Let the required fraction be x. Then	1	- x =	9
	x		20

∴	1 - x2	=	9
	x		20

  ⟹   20 - 20x² = 9x

  ⟹   20x² + 9x - 20 = 0

  ⟹   20x² + 25x - 16x - 20 = 0

  ⟹   5x(4x + 5) - 4(4x + 5) = 0

  ⟹   (4x + 5)(5x - 4) = 0

x =	4
	5

Correct Answer: 5

Explanation:

The pattern is -45, -35, -25, -15

The next number = 20-15= 5

Correct Answer: 42437

Explanation:

The square of a natural number never ends in 7.
42437 is not the square of a natural number

Correct Answer: 9944

Explanation:

To find the largest 4 digit number exactly divisible by 88,

We should divide the largest possible 4 digit number by 88, and if we get any remainder than subtract it from that largest number.

The largest possible 4 digit number is 9999

Now,

 

88) 9999 (113
      88
  _______
      119
        88
  _______
        319
        264
  _______
          55
  _______

 

Therefore, the largest 4 digit number exactly divisible by 88 is given by

9999 - 55 = 9944.

Correct Answer: 9

Explanation:

LCM of 2, 3, 7 is 42.

=> (700 ? 300)/42 = 9  22/42 => 9 Numbers.

Correct Answer: ¹²⁄₃₅

Explanation:

Let the numbers be a and b . Then, a + b = 12 and ab = 35.

∴	a + b	=	12	⟹	❨	1	+	1	❩	=	12
	ab		35			b		a			35

∴ Sum of reciprocals of given numbers =	12
	35

Correct Answer: 9