Quantitative Aptitude - Arithmetic Ability Questions

P(red ball) = 5/12

P(white ball) = 4/12

P(red or white ball) = 5/12 + 4/12 = 3/4 = 0.75

P=F1+in

Amount of work K can do in 1 day = 1/16

Amount of work L can do in 1 day = 1/12

Amount of work K, L and M can together do in 1 day = 1/4

Amount of work M can do in 1 day = 1/4 - (1/16 + 1/12) = 3/16 – 1/12 = 5/48

=> Hence M can do the job on 48/5 days = 9 (3/5) days  

I = Prt

Cash price = $3695

Deposit =1/3 of $3695 = $1231.67

Loan amount = $3695.00 − $1231.67 = $2463.33

Total cost of loan = $25.97 × 104= $2700.88

Interest charged = total amount − loan
I = A − P
= 2700.88 − 2463.33
= 237.55

Let the cost price of each mango be Rs. 1

So 50 mangoes costs = Rs. 50

20% Profit on Selling Price of 10 mangoes = Rs. 12 

30% Profit on Selling Price of 20 mangoes = Rs. 26

Total = Rs. 38

Loss = 50 - 38 = 12

Loss% = (12/50) x 100 = 24%.

Let S be the sample space and E be the event of selecting 1 girl and 2 boys.

Then, n(S) = Number ways of selecting 3 students out of 25

                = 25C3  = 2300.

         n(E)= 10C1*15C2 = 1050. 

P(E) = n(E)/n(s) = 1050/2300 = 21/46

Three digit number will have unit’s, ten’s and hundred’s place.

Out of 5 given digits any one can take the unit’s place.

This can be done in 5 ways. ...              (i)

After filling the unit’s place, any of the four remaining digits can take the ten’s place.

This can be done in 4 ways. ...              (ii)

After filling in ten’s place, hundred’s place can be filled from any of the three remaining digits.

This can be done in 3 ways. ... (iii) 

So,by counting principle, the number of 3 digit numbers = 5x 4 x 3 = 60