Quantitative Aptitude - Arithmetic Ability Questions

If tan4θ + tan2θ = 1 then the value of cos4θ + cos2θ is

A circle and a square have same area. The ratio of the side of the square to the radius of the circle will be:

X is 25% more efficient than Y. If Y alone can make a chair in 10 days, then X alone can make the chair in how many days?

10 persons can do a job in X days. If 20 persons with twice the efficiency can do the same job in 5 days, then find the value of X?

If 7 times the seventh term of an Arithmetic Progression (AP) is equal to 11 times its eleventh term, then the 18th term of the AP will be

The mean of the data 1, 2, 10, 18, 3, 17, 19 is

In ∆ ABC, the height CD intersects AB at D. The midpoints of AB and BC are P and Q respectively. If AD = 8 cm and CD = 6 cm, then the length of PQ is?

If [√(a2 + b2 + ab)] + [√(a2 + b2 – ab)] = 1, then what is the value of (1 – a2 )(1 – b2 )?