Quantitative Aptitude - Arithmetic Ability Questions

Let M litres milk be added

=> 60 + M40 = 31

=> 60 + M = 120

=> M = 60 lit.

Let the sum be Rs. x. Then

C.I=x[1+4/100)^2-x]=[626/675x-x]

S.I=x^2/25

C.I-S.I=1

Let the three parts M, N, O.
Then, M:N = 2:3 and N:O = 5:8
= (5 x 3/5) : (8 x 3/5) = 3:24/5

M:N:O = 2:3:24/5

= 10:15:24 => N = 98 x 15/49 = 30.

Let the sum invested be Rs. P

Let the rate of interest be R% per annum

=> Interest earned for 5 years = (P x 5 x R/100) = PR/20

Now, given that the interest earned increased by Rs. 600 if the Rate increased to (R+2)%

=> SI = (P x 5 x (R+2))/100 = PR/20 + 10P/100

Hence,

PR/20 + 10P/100 = PR/20 + 600

=> P = 6000

Therefore, the sum invested is Rs. 6000

Given monday population = 3000
Per day 20% increase in population.

Tuesday population = 3000 + 3000x20/100 = 3000 + 600 = 3600

Wednesday population =3600 + 3600x20/100 = 3600 + 720 = 4320

Thursday population = 4320 + 4320x20/100 = 4320 + 864 = 5184

So that day is Thursday.

Principal = Rs.16,000;

Time=9 months = 3 quarters;

Amount

=Rs.[16000x(1+5/100)³] =[16000x21/20x21/20x21/20]

= Rs.18522.

C.I

= Rs.(18522 - 16000)

= Rs.2522.

Let the original number is 82 i.e 8 + 2 = 10 and when the digits are reversed i.e 28
The difference is 82 - 28 = 54 i.e, the number is decreased by 54.

Length of train A = 48 x 9 x 5/18 = 120 mts

Length of train B = 48 x 24 x 5/18 - 120

=> 320 - 120 = 200 mts.