Quantitative Aptitude - Arithmetic Ability Questions

Time from 12 p.m on monday to 2 p.m on the following monday = 7 days 2 hours = 170 hours

Therefore, The watch gains 2+445 min. or  34/5 min. in 170 hrs.

Now, 34/5 min. are gained in 170 hrs.

Therefore, 2 min are gained in 170×534×2 hrs = 50 hrs

Therefore, Watch is correct 2 days 2 hrs. after 12 p.m on monday i.e it will be correct at  2 p.m on wednesday.

Speed on return trip = 150% of 50 = 75 km/hr.

Average speed = (2 x 50 x 75)/(50 + 75) = 60 km/hr.

The average age of a couple = 26 years.

Total age of couples = 26 x 2 = 52 years

 Total age of couple after 11 years = (52 + 2 * 11 ) = 74 years

Suppose average age of 3 children after 11 years is 3x years.

The average age of children is 7 years.

Length of the thread is 36 cms.
length wise twice breath wise once then totally thrice.
so 36/3 = 12.
so length is 12 x 2 = 24 cms
breath is 12 cms
Area of the book = length x breath = 24 x 12 = 288 sq.cm

Given the angles of a quadrilateral are in the ratio of 2:4:7:5
Let the angles of a quadrilateral are 2x, 4x, 7x, 5x
But we know that sum of the angles = 360 degrees.
=> 2x + 4x + 7x + 5x = 360
=> x = 20
Therfore, the smallest angle of the quadrilateral = 2x = 2x20 = 40 degrees.
One of the angle of the triangle = 2 x 40 = 80 degrees
The other angle is 180 - (40 + 80) = 60 degrees.

Hence the second largest angle of the triangle is 60 degrees.

Suppose A, B and C take x, x/2 and x/3 respectively to finish the work.
Then, (1/x + 2/x + 3/x) = 1/2
6/x = 1/2 => x = 12
So, B takes 6 hours to finish the work.

60(x + 1) = 64x

X = 15

60 x 16 = 960 km

Here in 100P2, P says that permutations and is defined as in how many ways 2 objects can be selected from 100 and can be arranged.

That can be done as,

100 P2 = 100!/(100 - 2)!

= 100 x 99 x 98!/98!

= 100 x 99 

= 9900.