Quantitative Aptitude - Arithmetic Ability Questions

The average marks of 40 students in an examination was 34. It was later found that the marks of one student had been wrongly entered as 62 instead of 26. what is the correct average?

Gurkiran's birthday is on Sunday 21st May. On what day of the week will be Shreyas's Birthday in the same year if Shreyas was born on 14th November?

A can finish a work in 7 days . B can finish the same work in 9 days . The days required to finish the work by both of them together.

If a+b=2c then the value of aa-c+cb-c is equal to (where a≠b≠c)

P and Q are two alloys which are prepared by mixing tin and lead in the ratio of 12 : 5 and 4 : 3 respectively. If equal quantities of alloys are melted to form athird alloy R, then what is the ratio of tin and lead in alloy R?

The standard deviation of the set {10, 11, 9, 11, 9} is

A can do a work in 36 days and B in 12 days. If they work on it together, then in how many days will they be able to do the work?

Three bottles of equal capacity containing mixture of milk and water in ratio 2 : 5, 3 : 4 and 4 : 5 respectively. These three bottles are emptied into a large bottle. What will be the ratio of milk and water respectively in the large bottle?