Quantitative Aptitude - Arithmetic Ability Questions

Which among the following is true for the given numbers?

Diameter of wheel of a cycle is 21 cm. The cyclist takes 45 minutes to reach a destination at a speed of 16.5 km/hr. How many revolutions will the wheel make during the journey?

ΔXYZ is similar to ΔPQR. If ratio of Perimeter of ΔXYZ and Perimeter of ΔPQR is 4:9 and if PQ = 27 cm, then what is the length of XY (in cm)?

Two donkeys are standing 400 meters apart. First donkey can run at a speed of 3 m/sec and the second can run at 2 m/sec. If two donkeys run towards each other after how much time (in sec) will they bump into each other?

If x2+1x2-6, then find the value of 2x(x-1)x3-x2-x+1

The sum of three numbers is 252. If the first number is thrice the second and third number is two-third of the first, then the second number is

The value of 8(sin6θ + cos6θ) - 12(sin4θ + cos4θ) is equal to

Simplify 437bxaz / 23ab.