Quantitative Aptitude - Arithmetic Ability Questions

The given number series is 120, 36, 6, 2, 1, 1

120

120/5 = 24 (not 36)

24/4 = 6

6/3 = 2

2/2 = 1

1/1 = 1

Hence, the odd man in the given number series is 24.

Given number series is 61, 66, 83, 121, 185

Here the given series follows a pattern that,

$$\begin{gathered} 61 \\ 61 + 22 + 1 = 66 \\ 66 + 42 + 1 = 83 \\ 83 + 62 + 1 = 120 (not 121) \\ 120 + 82 + 1 = 185 \end{gathered}$$

Hence, the odd man in the given series is 121.

Lets say shyam sells at 100,

Since Ram sells 25% cheaper than Shyam,

Therefor Ram sells at less than 25% of100 or 75 rs.

Ram sells 25% dearer than Bram or 125% of Ram =100% of Bram or

125% of x (say x price of bram )=75rs.
or 100% of x =60rs.
hence price of bram is 60rs.

now Bram's good is cheaper than Shyam's as (100-60)x100/100% or 40%.

Hence Brams Good is 40% cheaper than that of Shyam's good.

Product of numbers = 11 x 385 = 4235

Let the numbers be 11a and 11b . Then , 11a x 11b = 4235  =>  ab = 35

Now, co-primes with product  35 are (1,35) and (5,7)

So, the numbers are ( 11 x 1, 11 x 35)  and (11 x 5, 11 x 7)

Since one number lies 75 and 125, the suitable pair is  (55,77)

Hence , required number = 77

5 : 4 = 5/4 = ( (5/4) x 100 )% = 125%.

The given number series is 8, 16, 20, 36, 68

8

8 x 2 - 4 = 12 (NOT 16)

12 x 2 - 4 = 20

20 x 2 - 4 = 36

36 x 2 - 4 = 68

Hence, the odd man in the given series is 16.

Pass percentage  =[(252/270)*100] % =280/3 % =9313 9 %

It is given that last three digits are randomly dialled. then each of the digit can be selected out of 10 digits in 10 ways.
Hence required probability =1103 = 1/1000