Quantitative Aptitude - Arithmetic Ability Questions

Let the total amount be 200 {L.C.M of 40 and 50}

Chacobar C.P. = 200/50 = 4

Fivestar C.P = 200/40 = 5

Remaining Money after petrol = [200 - 200×10%] = 180

Remaining money after buying fivestars = [180 - 20×5] = 80

So number of Chacobar she can buy = 80/4 = 20

The number of letters in the given word CREATIVITY = 10

Here T & I letters are repeated

=> Number of Words that can be formed from CREATIVITY = 10!/2!x2! = 3628800/4 = 907200

Total number of possible ways = 

9C5 = 9 x 8 x 7 x 6 x 55 x 4 x 3 x 2 x 1 = 126

Number of favorable cases = 

$$\begin{gathered} 4C2 x 5C3 + 4C3 x 5C2 + 4C4 x 5C1 \\ 4 x 32 x 1 x 5 x 4 x 33 x 2 x 1 + 4 x 3 x 23 x 2 x 1 x 5 x 4 2 x 1 + 1 x 5 \\ = 6 x 10 + 4 x 10 + 5 \\ = 60 + 40 + 5 \\ = 105 \end{gathered}$$

Therefore, required probability = 105/126 = 5/6

Since order does not matter, use the combination formula 

C34 = 24/6 = 4

Time taken to cover 600 km = 600/100 = 6 hrs.

Number of stoppages = 600/75 - 1 = 7

Total time of stoppages = 4 x 7 = 28 min

Hence, total time taken = 6 hrs 28 min.

From given data,

(C.P. of 17 balls) - (S.P. of 17 balls) = (C.P. of 5 balls)

C.P. of 12 balls = S.P. of 17 balls = Rs.720.

Hence, C.P. of 1 ball = Rs.720/12 = Rs. 60.