Quantitative Aptitude - Arithmetic Ability Questions

Seven years ago, the age of Sahil was equal to the present age of Nihal. Sum of Sahil's age 5 year ago and Nihal's age 6 years later is 58 years. If Ruchi is 4 years elder to Sahil, then what will be Ruchi's age (in years) after 10 years?

If a + a2 + a3 – 1 = 0, then what is the value ofa3 + (1/a)?

Raja and Kundan together can build a wall in 20 days, Kundan and Mahesh build the same wall in 30 days and Mahesh and Raja can build the same wall in 24 days. In how many days can all the three complete the same wall while working together?

An alloy is made by mixing metal A costing Rs 2000/kg and metal B costing Rs 400/kg in the ratio A:B = 3:1. What is the cost (in Rs) of 8 kilograms of this alloy?

What is the value of sinAtanA/(1 - cosA)?

If (X/4) = (Y/5) = (Z/9), then what is X : Y : Z?

Which one is the largest among the fractions (5/113), (7/120), (13/145) and (17/160)?

If the number 583_437 is completely divisible by 9, then the smallest whole number in the place of the blank digit will be