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?

A sum of money (P) doubles in 10 years. How much would it be in 20 years at the same rate of simple interest?

If 2+x+2-x2+x-2-x=2,then the value of X is

Find the curved surface area (in cm2) of a right circular cylinder of diameter 28 cm and height 12 cm.

P and Q together can make a door in 12 days. They started the work together but after 8 days P left the work. The remaining work is completed by Q alone in 7 more days. In how many days can P alone complete the entire work?

In ΔABC, D and E are points on side AB and AC respectively. DE is parallel to BC. If lengths of AD, DB and DE are 9 cm, 6 cm and 5.4 cm respectively find length of BC?

The point R(a,b) is first reflected in origin to R1 and R1 is reflected in x-axis to (-3,4). The co-ordinates of point R are

If a = 5, b = 4, c = 8 then find the value of (a3 + b3 + c3 - 3abc)/(ab + bc + ca - a2 - b2 - c2)