For any real value of $${\sqrt {secθ-1}\over \sqrt {secθ+1} }=?$$

10 men working 6 hours a day can complete a work in 18 days. How many hours a day must 15 men work to complete the same work in 12 days?

When a shopkeeper gives 10% discount on the list price of a toy, his gain is 20%. If he had given a discount of 20%, his percentage of gain would have been 

In Δ ABC, D and E are points on AB and BC, respectively, such that DE is parallel to AC. If DE = 3 cm, AC = 5 cm and the area of trapezium ACED = 32 cm2, then what will be the area of Δ BDE?

if $${secA={5\over 4}}$$, then the value of $${{tanA}\over 1+tan^2A}-{sinA\over secA}$$ is

A and B start moving towards each other from places X and Y, respectively, at the same time on the same day. The speed of A is 20% more than that of B. After meeting on the way, A and B take p hours and 72 hours, respectively, to reach Y and X, respectively. What is the value of p?

Remi earns a profit of 20% on selling an article at a certain price. If she sells the articles for ₹8 more, she will gain 30%. What is the original cost price of 16 such articles?

A trader buys a hand watch for Rs.450 and determines its marked price in such a way that even after allowing a discount of 10% on that watch, he makes a profit of 20%. What is the marked price of the watch?