Quantitative Aptitude - Arithmetic Ability Questions

The traffic lights at four different road crossings change after every 15 sec, 18 sec, 27 sec and 30 sec respectively. If they all change simultaneously at 6:10:00 hours, then at what time will they again change simultaneously?

Two numbers are 40% and 50% lesser than a third number. By how much percent is the second number to be enhanced to make it equal to the first number?

The inradius of a equilateral triangle is 10 cm. What is the circum-radius (in cm) of the same triangle?

If aq-r+br-p-cp-q, then find the value of (pa + qp + rc) is

Reflection of the point (-3,6) in the x-axis is

Δ ABC is right angled at B. If m∠A = 60°, then what is the value of sec C.sin A?

The ratio of salary of X, Y and Z is 15 : 3 : 8. If Z gets Rs. 3960 more than Y, then what is the salary (in Rs.) of X?

ΔDEF is right angled at E. If secD = 25/7, then what is the value of cosecF ?