Quantitative Aptitude - Arithmetic Ability Questions

The ratio of the ages of two boys is 3:4. After 3 years, the ratio will be 4:5.The ratio of their ages after 21 years will be

Every month, Kritika spends 30% of her income on house rent and 60% of the rest on household expenditure. If she saves ₹ 6300 per month, what is her total monthly income?

If the price of pen decreases by 20%, then a man can buy 10 more pens for Rs 100. What is the new price (in Rs) of each pen?

If 1 + (1/2) + (1/3) + ... + (1/20) = k, then what is the value of (1/4) + (1/6) + (1/8) + ... + (1/40)?

A certain sum of money amounts to Rs 918 in 2 years and Rs 969 in 3.5 years at simple interest. What is the rate of interest (in %)?

Rajeev sells a machine for Rs 55 lakhs at a loss. Had he sold it for Rs 67 lakh, his gain would have been 5 times the former loss. Find the cost price of the machine.

If 27x + 27[x–(1/3)] = 972, then what is the value of x?

A number is increased by 84, it becomes 107% of itself. What is the number?