Quantitative Aptitude - Arithmetic Ability Questions

The given number series 2676, 445, ?, 21,6, 2, 1 follows a pattern that,

From right side,

1

1 x 1 + 1 = 2

2 x 2 + 2 = 6

6 x 3 + 3 = 21

21 x 4 + 4 = 88

88 x 5 + 5 = 445

445 x 6 + 6 = 2676

Hence the missing number in the given number series is 88.

Given numbers are 1.08 , 0.36 and 0.90

 H.C.F of 108, 36 and 90 is 18                  [ ∵ G.C.D is nothing but H.C.F]

 Therefore, H.C.F of given numbers = 0.18                 

The given number series is 3, 11, 80, 291, 803

$$\begin{gathered} 3 \\ 3 + 23 = 3 + 8 = 11 \\ 11 + 43 = 11 + 64 = 75 (not 80) \\ 75 + 63 = 75 + 216 = 291 \\ 291 + 83 = 291 + 512 = 803 \end{gathered}$$

Let the required length be x meters

 More men, More length built     (Direct proportion) 

Less days, Less length built      (Direct Proportion)

Men20:35Days6 : 3⋮⋮ 56 :x 

=> (20 x 6 x X)=(35 x 3 x 56) 

=> x = 49 

Hence, the required length is 49 m.

Explanation:

Let rate = R% and time = R years.

Then, 1200*R*R100=432

12R2=432

=>R2=36⇔R=6

Excess of B's height over A's = [(40/(100 - 40)] x 100% =  66.66%