Quantitative Aptitude - Arithmetic Ability Questions

i=j/m

FV
= PV(1 + i)^n

Let A's age 10 years ago be x years . Then B's age 10 years ago be 2x years

 Total of their present ages = x + 10 + 2x + 10

= 3x+20

= 3 * 5 + 20 = 35 years

$$\begin{gathered} 0.01+0.0064=0.01+6410000 \\ =0.01+8100 =0.01+0.08=0.3 \end{gathered}$$

If Jason is on th ecouncil,this reduces the selction pool to only 13 people,out of which we still need to select 4.

So, 13C4 = 715

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

From the given data,

P = 140

But it is given that,

40% of Q + Q = 140 = P

=> Q + [40Q/100] = 140

=> [100Q + 40Q]/100 = 140

=> 140Q = 140 x 100

=> Q = 100

Now,

 3/25 of Q 

= (3/25) x 100

= 3 x 4 

= 12 

Required 3/25 of Q  = 12.

Clearly, Rate = 5% p.a .,

Time = 3 years

S.I =Rs.1200.

So,Principal

=Rs.(100 x 1200/3x5)

=Rs.8000.

Amount

=Rs.[8000 x (1+5/100)³]

=Rs(8000x21/20x21/20x21/20)

= Rs.9261

C.I

=Rs.(9261-8000)

=Rs.1261.

Here 40% of 80 is given as

40100 x 80 = 8 x 4 = 32