Quantitative Aptitude - Arithmetic Ability Questions

End of first year     :  10000 x (3/5) = Rs. 6000
End of second year :  6000 x (3/5) = Rs. 3600
End of third year    :  3600 x (3/5) = Rs. 2160

Given total students in the class = 60
Students who are taking Economics = 24 and
Students who are taking Calculus = 32
Students who are taking both subjects = 60-(24 + 32) = 60 - 56 = 4
Students who are taking calculus only = 32 - 4 = 28
probability that a randomly chosen student from this group is taking only the Calculus class = 28/60 = 7/15.

Let the age of the youngest child is 'X' years.
Then the child elder than the yongest is 'X + 3' yrs
Since each have 3yrs difference upto 5 children
And given that
=> X + X+3 + X+6 + X+9 + X+12 = 50
=> 5X + 30 = 50
=> X = 4 yrs.

4 persons can be selected from 9 in 9C4 ways =126

Fvaourable events =4C2*5C2 =60

So,required probability = 60/126 = 10/21

i=j/m

FV
= PV(1 + i)^n

$$\begin{gathered} log3437 \\ log737 \\ 13log77 \\ We know that logxx = 1 \\ => 13 \end{gathered}$$

Less toys, Less Price (Direct Proportion)
So, let the price be Rs. x
then,

             23:12::276:x    => x=(276*12)/23

                                    => x=144

So price of 12 toys will be Rs. 144