Quantitative Aptitude - Arithmetic Ability Questions

Let their ages be x, y, z
Hence given that x + y + z = 65
Now, six years ago x age is x - 6, y is y - 6 and that of z is z - 6
Then the sum of their ages six years ago is (x + y + z) - (6 + 6 + 6) = 65 - 18 = 47

$$\begin{gathered} Given 3.2% of 500 × 2. 4% of ? = 312 \\ Then, \\ 3.2 x 500100 x 2.4 x ?100 = 312 \\ 16 x 2.4x?100 = 312 \\ 9.6 x ?25 = 312 \\ 9.6 x ? = 7800 \\ ? = 78009.6 \\ ? = 812.5 \end{gathered}$$

This question is a combination since order is not important.

Answer = 7C3 = 126

Given that three athletes can complete one round around a circular field in 16, 24 and 36 min respectively.

Now, required time after which they met for the first time = LCM of (16, 24 & 36) min

Now, LCM of 16, 24, 36 = 144 minutes = 2 hrs 24 min.

BG=TD2PW=(340)23400=Rs.34

With slight modifications, the basic formula can be made to deal with compounding at intervals other than annually.

Since the compounding is done at six-monthly intervals, 4 per cent (half of 8 per cent) will be added to the value on each occasion.

Hence we use r = 0.04. Further, there will be ten additions of interest during the five years, and so n = 10. The formula now gives:

V = P(1 + r)10 = 5,000 x (1.04)10 = 7,401.22

Thus the value in this instance will be £7,401.22.

In a case such as this, the 8 per cent is called a nominal annual

rate, and we are actually referring to 4 per cent per six months.