Quantitative Aptitude - Arithmetic Ability Questions

1/K + 1/L + 1/M = 1/8 (Given)
Also given that K = 2L and L = 2M
=> 1/2L + 1/L + 2/L = 1/8
=> (1 + 2 + 4)/2L = 1/8
=> 2L/7 = 8
=> L = 28 hours.

CAPITAL = 7

Vowels = 3 (A, I, A)

Consonants = (C, P, T, L)

5 letters which can be arranged in  5P5=5!

Vowels A,I = 3!2!

No.of arrangements = 5! x 3!2!=360

Given K=4L 

-->K+L = 4L+L = 5L

These 5L people can complete the work in 24 days, which means L alone can do the work in (24 x 5)=120 days.

Hence, K alone can do the work in 120/4= 30 days.

There are 13 spades,we must include 2: 13C2

There are 13 diamonds,we must include 3: 13C3

Since we can't have more than 2 spades and 3 diamonds,the remaining 2 cards must be pulled out from the 26 remaining clubs and hearts : 26C2

Therefore,13C2*13C3*26C2 = 7250100

1st day the girl read = 40%

2nd day she read = 34 %

Remaining percentage of book = 100% - (40% +34%) = 26%

But given last two days she read equal number of pages

=> Each day she read 26%/2 = 13%

Last day she read 52 pages = 13%

13% = 52

1% = 4

=> 100% = 400

Total pages in the book is 400.

2(l+b)/b = 5/1 

=> 2l + 2b = 5b  

=> 3b = 2l  

=> b =(2/3) x l

 Then, Area = 216 sq.cm 

l x b = 216  

=> l x [(2/3)x l] =216  

=> l x l = 324 

=> l = 18 cm.

First we need to choose two vowels 3C2 and then three consonants 5C3. Now that we have 5 letters required to make the word,arrange them in 5! ways.

So,3C2*5C3*5! = 3600

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