Quantitative Aptitude - Arithmetic Ability Questions

If the average age of four children is 12 years and the average age of these children and their fathers is 20 years, what is the age of the father?

Twenty women can do a work in sixteen days. Sixteen men can complete the same work in fifteen days. The ratio between the capacity of a man and a woman is

A work can be completed by 18 boys in 24 days. If 6 boys leave after working for 12 days, then how many days will be needed to complete the remaining work?

If  x = 2+3,then what is the value of 2x + 12x ?

If x + [1/(x + 7)] = 0, then what is the value of x – [1/(x + 7)]?

In what ratio rice costing Rs 14/kg mixed with another rice costing Rs 11/kg to get the mixture costing Rs 11.6/kg?

The mean of marks secured by 45 students in division A of class X is 69, 65 students of division B is 65 and that of 50 students of division C is 63. Find the mean of marks of the students of three divisions of Class X.

What is the slope of the line parallel to the line passing through the points (-2, -1) and (4, -3)?