Quantitative Aptitude - Arithmetic Ability Questions

A, B and C can do a job working alone in 50, 75 and 20 days respectively. They all work together for 4 days, then C quits. How many days will A and B take to finish the rest of the job?

In how many different ways can the letters of the word 'THERAPY' be arranged so that the vowels always come together?

In a school , 391 boys and 323 girls have been divided into the largest possible equal classes , so that each class of boys numbers the same as each class of girls . What is the number of classes ?

How many numbers are there from 2000 to 7000 which are both perfect squares and perfect cubes?

The population of a town increases by 5% in the first year, by 6% in the second year and by 8% in third year. The present population of town is 120204. What was the population of the town 3 years ago?

If tan 45° + cosec 30° = x, then find the value of x.

The average of marks of 17 students in an examination was calculated as 71. But it was later found that the mark of one student had been wronglyentered as 65 instead of 56 and another as 24 instead of 50. The correct average is

If 2x + 3y – 5z = 18, 3x + 2y + z = 29 and x + y + 3z = 17, then what is the value of xy + yz + zx?