Quantitative Aptitude - Arithmetic Ability Questions

Let the ratio of initial quantity of oils be 'x' => 4x, 5x & 8x.
Let k be the quantity of third variety of oil in the final mixture.
Let the ratio of initial quantity of oils be 'y'
From given details,
4x + 5 = 5y ..... (1)
5x + 10 = 7y .....(2)
8x + k = 9y ......(3)

By solving (1) & (2), we get
x = 5 & y = 5

From (3) => k = 5

Therefore, quantity of third variety of oil was 9y = 9(5) = 45kg.

Given number of balls = 3 + 5 + 7 = 15

One ball is drawn randomly = 15C1

probability that it is either pink or red = 7C1 + 3C115C1 = 7 + 315 = 1015 = 23

Let the price of an item be 100After 25% decrease, price of item = 75Increase in price to get the original price = 100-75 = 25% increase to get the original price = 25/75 X 100 = 100/3 = 33.33%

Because each vertice of the square is the center of a circle
(1/4) part of the total area of each circle inside of the square.
(3/4) part of the total area of each circle outside of the square.
Thus total area outside the square is 434×227×3.5×3.5 = 115.3955 sq cm.

28 May, 2006 = (2005 years + Period from 1.1.2006 to 28.5.2006)

Odd days in 1600 years = 0

Odd days in 400 years = 0

5 years = (4 ordinary years + 1 leap year) = (4 x 1 + 1 x 2) 6 odd days

Jan. Feb. March April May

(31 + 28 + 31 + 30 + 28 ) = 148 days

148 days = (21 weeks + 1 day) 1 odd day.

Total number of odd days = (0 + 0 + 6 + 1) = 7 0 odd day.

Given day is Sunday.

12 year old Manish is three times as old as his brother Rajeev who must be 4 years old.
Diff in ages = 8 years.
when Rajeev will become 8 years old, Manish will be 16 yrs old and he will be twice as old as Rajeev.