Quantitative Aptitude - Arithmetic Ability Questions

If N = 0.369369369369... and M = 0.531531531531..., then what is the value of (1/N) + (1/M)?

What is the rate of interest (in %) if simple interest earned on a certain sum for the 3 years is Rs 6,000 and compound interest earned for 2 years is Rs 4,160?

A student multiplied a number by 4/7 instead of 7/4. What is the percentage error in the calculation?

In the question given below, two equations are provided. Solve the equations and establish the relationship between x and y

$$\begin{gathered} I. 2x2-13x-189=0 \\ II. 2y2-3y-189=0 \end{gathered}$$

A shopkeeper marks up his wares by 125% and offers 25% discount. What will be the selling price if the cost price (in Rs) is Rs 640?

Find out the odd word/letters/number/number pair from the given alternatives.

Rithika had Rs 8000. She invested some of it in savings scheme P and the rest of the money in savings scheme Q. She invested for 3 years in savings scheme P and for 2 years in savings scheme Q. savings scheme P offers SI at a rate of 20% pa while savings scheme Q compounded annually at the rate of 30% pa. The interest received from savings scheme P is 930 more than the interest received from savings scheme Q. If Rs 1500 is debited from the invested amount of savings scheme P then find the difference between the amount invested by Rithika in savings scheme P & savings scheme Q.

The standard deviation of the set {10, 10, 10, 10, 10} is