Quantitative Aptitude - Arithmetic Ability Questions

S=R[(1+i)^n-1)/i]

15! - 14! - 13!

= (15 × 14 × 13!) - (14 × 13!) - (13!)

= 13! (15 × 14 - 14 - 1)

= 13! (15 × 14 - 15)

= 13! x 15 (14 - 1)

= 15 × 13 × 13!

Cost of 4 mangoes = Rs. 6 

Cost of 1 mango = Rs. 6/4 = Rs. 1.5

Now, Selling Price of 4 mangoes = Rs. 4

Selling Price of 1 mango = Rs. 4/4 = Rs. 1.0

• We observe that, S.P < C.P

Hence, the shopkeeper incurs a loss.

Required loss% = loss/C.P x 100

Loss = 1.5 - 1 = 0.5

C.P = 1.5

Loss% = (0.5/1.5) x 100

 = (5/15) x 100

 = 1/3 x 100

 = 100/3

 = 33.333%.

The ratio of money she lended is

24000 : 16000 = 3 : 2

Let the rate of interest be R%

8%                   R%
     

           10

3          :           2

R = 13%.

We know 60 min = 1 hr
Total northward Laxmi's distance = 20kmph x 1hr = 20 km
Total southward Prasanna's distance = 30kmph x 1hr = 30 km
Total distance between Prasanna and Laxmi is = 20 + 30 = 50 km.

Let rate = R% and time = R years.

Then, (1200 x R x R) / 100 = 432

=> R = 6.

Monday + Tuesday + Wednesday = 37 x 3 -----------(1)
Tuesday + Wednesday + Thursday = 34 x 3---------(2)
Thursday = 4/5 of Monday ------------------(3)
subtract eqn (1) from (2) we get,
Thursday - Monday = -9
=> Monday - Thursday = 9.......(4)
From (3) & (4), we get

So,Thursday = 36 C

M = 10 days

The ratio of efficiency of M & N are 3 : 2

Hence, the time rquired for N alone = 15 days

=> Required time taken t=by both to complete the work = M x N / M + N 

= 10 x 15/ 10 + 15

= 150/25

= 6 days.