Quantitative Aptitude - Arithmetic Ability Questions

Find the value of '?' in 512 × 125 ÷ 15625 = 3125 × 25?

The value of 122 + 345 - 3 / 1116 x 372 is

Find length of the arc whose central angle is 90° and radius of the circle is 3.5 cm?

If 4x2 - 12x + k is a perfect square, then the value of k is

A and B can complete a task in 20 days, B and C can complete it in 30 days while C and A can do the same task together in 24 days. How many days will each of and C take to complete the task individually? 

A train starts moving from a place X at 7:00 a.m. and arrives at another place Y at 1:00 p.m. on the same day. If the speed of the train is 15 m/s, then what will be the distance (in km) covered by the train?

The diagonals do not form at least two congruent triangles in a _____.

What is the diameter (in cm) of a sphere of surface area 154 sq cm?