A is older by 4 years to B at one stage. After 16 years of this stage, A will be thrice his present age and B will be five times his present age. How old would A and B be two years before the initially indicated stage?

Yes, Every integer is a rational number.  A rational number is a number which can be expressed as a ratio of two integers numerator and denominator where (the denominator not being 0 ).

Hence, Every integer can be expressed in ratio of two integers. 

Fruits reduced by 1/4.
Total no. of bags N = 5
Formula to find no. of fruits in 1st bag = 4^n
Last Bag = 4 fruits.
That means, 4th bag = 4 x 4 = 16 fruits
3rd bag = 16 x 4 = 64 fruits
2nd bag = 64 x 4 = 256 fruits
1st bag = 256 x 4= 1024 fruits.

We all know about BODMAS rule, by using that

3x3x3+3+3/3

= 3x3x3+3+1

= 27+3+1

= 27 + 4

= 31

Hence,  3x3x3+3+3/3 = 31.

Number - '79246358' If the digits are arranged in descending order from left to right, new number = 98765432 Difference between the digits which are third from the right and second from the left = 8 - 4 = 4.

Perimeter = 36

? 2 ( l + w ) = 36

? l + w = 18

Since length and width are positive integers in centimeters.

Therefore, possible dimensions are :

( 1, 17 )cm , ( 2, 16 ) cm , ( 3, 15 ) cm, (4 , 14) cm, ( 5,13) cm, ( 6, 12) cm , ( 7, 11) cm, ( 8, 10 ) cm, ( 9, 9) cm.

Hence, there are 9 rectangles.

We know that, any decimal number when multiplied by the multiples of 10, the decimal point moves to right the number of zeroes in the multiplying number.

For example :: 

0.0410 x 100 = 4.10 (Number of zeros in 100 are 2. So, the decimal point in 0.0410 moves two places to the right and becomes 4.10.)

Similarly, here in the option C) 5.008 x 10^3 kms it makes 5008 kms as the number of zeros in 10^3  i.e,  1000 are 3 and 5.008 becomes 5008.