Quantitative Aptitude - Arithmetic Ability Questions

In an alloy, aluminium and tin are in the ratio of 4 : 5. In the second alloy, the ratio of same elements is 4 : 7. If equal quantities of these two alloys be mixed to form a new alloy, then what will be the ratio of both of these elements in the new alloy?

What is the average of first 19 odd numbers?

A, B and C can do a job working alone in 12, 16 and 24 days respectively. In how many days they can do the job if they worked together?

What is the ratio of radius of incircle and circumcircle for an equilateral triangle with an area of 22√3 sq. units?

The income of S, T and U are in the ratio of 7 : 9 : 6 and their expenses in the ratio of 4 : 5 : 3. If S saves Rs 2000 out of an income of Rs 14000, then what will be the saving (in Rs) of T?

A box consist of 5 rupees, 2 rupees and 1 rupee coins and their value are in the ratio of 15 : 4 : 2 respectively. If there are total 112 coins, then how many 2 rupees coins are there in the box?

What is the equation of the line which passes through the points (3,­2) and (5,3)?

2sin[(C+D)/2].cos[(C­-D)/2] is equal to