Quantitative Aptitude - Arithmetic Ability Questions

Let the present age's of mother be 'M' and that of her son be 'S'.

According to the given data in the question,

M - 5 = 3(S - 5)

F - 3S = -10  ...............(1)

Then given ,

M + 5 : S + 5 = 11 : 5 

=> 5M - 11S = 30 ..............(2)

From (1) & (2), we get

S = 20

Then by substituting S = 20 in (1) or (2), we get

M = 50.

Hence, the present age of mother is M = 50 years.

10% profit at half plot = 600000/2 x 10/100 = Rs. 30,000

15% profit at remaining half plot = 600000/2 x 15/100 = Rs. 45,000

Now, total profit = 30000 + 45000 = 75000

Profit % = 75000/600000 x 100 = 12.5 %

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

The single equivalent payment will be PV + FV.
FV
= Future value of $10,000, 12 months later

$10,000 *(1.0075)/12

$10,938.07
PV=
Present value of $10,000, 24 months earlier

$10,000/(1.0075)24

$8358.31
The equivalent single payment is
$10,938.07 + $8358.31
= $19,296.38

S.I. for 2 years = (514 - 415) = Rs. 99
S.I. for 1 year = 99/2

Principal = (415 - 99) = Rs. 316.