Quantitative Aptitude - Arithmetic Ability Questions

On walking 100 metres towards a building in a horizontal line, the angle of elevation of its top changes from 45 to 60 deg. What will be the height (in metres) of the building?

A train crossed a 140 m long platform in 15 seconds and a 180 m long platform in 17 seconds. The speed of the train was

The average age of 19 boys in a class is 21 years. If the teacher's age is included, the average increases to 22 years. What is the teacher's age?

(1132 + 1152 + 1172 - 113 x 115 - 115 x 117 - 117 x 113) is equal to

Among three numbers, the first is twice the second and thrice the third. If the average of three numbers is 198, then what is the difference between the first and the third number?

If a + b = 8 and ab =15, then a3 + b3 is

Find the value of 777777?

If xy+yz+zx = 1, then the value of (1+y2)(x+y)(y+z) ?