Quantitative Aptitude - Arithmetic Ability Questions

A and B can together complete a task in 18 hours. After 6 hours A leaves. B takes 36 hours to finish rest of the task. How many hours would A have taken to do the task if he worked alone?

The average age of a class of 6 girls is x years. Four new girls having ages x – 2, x + 2, x + 4 and x + 6 joins the class. What is the new average age (in years) of the class?

Of the 3 numbers whose average is 22, the first is 3/8th the sum of other 2. What is the first number?

The marked price of an article is 10/7 of the cost price and the selling price of that article is 4/5 of the marked price. What is the profit percentage?

What approximate value should come in place of the question mark (?) in the following questions? (You are not expected to calculate the exact value.)

21.003 × 39.998 –209.91 = 126× ?

In a triangle the length of the side opposite the right angle is 9√3 cm, what is the length of the side opposite to the angle which measures 30 degree?

Three categories of employees get wages in the ratio of 1 : 2 : 3. If they get increments of 5%, 10% and 15% respectively, what will be the new ratio of their wages?

∆XYZ is right angled at Y. If tanX = 24/7, then what is the value of cotZ ?