Quantitative Aptitude - Arithmetic Ability Questions

Clearly, there are 52 cards, out of which there are 12 face cards.

P (getting a face card) = 12/52=3/13.

One way to deal with fractions is to convert them all to decimals. 

In this case all you would need to do is to see which is greater than 0.5.

Otherwise to see which is greater than ½, double the numerator and see if the result is greater than the denominator. In B doubling the numerator gives us 8, which is bigger than 7. 

This can be easily simplified by Approximation process

Given 39.96% of 649.85 ÷13.07 = 45.14 - ? can be written as 

40% of 650 ÷13 = 45 - ?

$$\begin{gathered} 40 x 65010013 = 45 - ? \\ ? = 45 - 20 \\ ? = 25. \end{gathered}$$

Here the series follows the pattern that, product of succesive prime numbers i.e,

 2 × 3 = 6

 3 × 5 = 15

 5 × 7 = 35

 7 × 11 = 77

 11 × 13 = 143

 13 × 17 = 221

 17 × 19 = 323

So here in place of 77 the number 63 is written.

So the wrong number is 63.

Here the given series 28, 12, 4, 2, -2 follows a pattern that

$$\begin{gathered} 28 \\ 28 - 24 = 28 - 16 = 12 \\ 12 - 23 = 12 - 8 = 4 \\ 4 - 22 = 4 - 4 = 0 (NOT 2) \\ 0 - 21 = 0 - 2 = -2 \end{gathered}$$

Hence, the odd man in the given series is 2.

Let sum=Rs.x

C.I. when compounded half yearly = x1+101004-x=464110000

C.I. when compounded annually =x201002-x=1125

 464110000x-1125x=482

=> x=20000

Let the salaries of A, B, C be x, 2x and 3x respectively.

Then,2x + 3x = 6000  => x = 1200.

A's salary = Rs. 1200, B's salary = Rs. 2400, and Cs salary Rs. 3600.
Excess of C's salary over A's=[ (2400 /1200) x 100] = 200%.