Aptitude and Reasoning Questions

 Since 8 does not occur in 1000, we have to count the number of times 8 occurs when we list the integers from 1 to 999. Any number between 1 and 999 is of the form xyz, where 0≤x,y,z≤9.

Let us first count the numbers in which 8 occurs exactly once.

Since 8 can occur atone place in 3C1ways. There are 3 x 9 x 9 such numbers.

Next, 8 can occur in exactly two places in 3C2×9 such numbers. Lastly, 8 can occur in all three digits in one number only.

Hence, the number of times 8 occur is 

 1×3×92+2×3×9+3×1 = 300

Given 

4 45 of 259.99 = ? % of 1247.9

24/5 x 260 = ? x 1248/100

? = 1248 x 100/1248

? = 100.

PW = 100×Amount100+R×T 

Speed = 108 km/hr
enter a tunnel,, means that the train covers a distance equal to its own length
so (108 x 5/18) = x/4 where x= length of train
hence x = 120 mtrs
to pass completely train has to travel a distance = (x + tunnel length) that is 1120 mtrs.
so (1120/t) = (108x5/18)
t = 37.33 sec

1. To find the interest, subtract the principal from the balance.

       $618 - $600 = $18

2.Use the simple interest formula and solve for r.

       I = Prt

      18= 600 x r x (1/2)

       r= 0.06 =6%

A line is an undefined term because of it :

1. Contains an infinite number of points

2. can be used to create other geometric shapes

3. is a term that does not have a formal definition

In Geometry, unless it's stated, a line will extend in one dimension and goes on forever in both ways.

Area to be plastered= [2(l + b) x h] + (l x b)

= [2(25 + 12) x 6] + (25 x 12)  

= (444 + 300)  

= 744 

Cost of plastering = Rs. 744 x (75/100)= Rs. 558