Quantitative Aptitude - Arithmetic Ability Questions

If cosαcosβ=m and cosαsinβ=n,then the value of m2+n2 cos2β is

If x2+y2+z2-8x+6y-4z+29 = 0, then find the value of z(x+y).

Findout the odd word/letters/number/number pair from the given alternatives.
7 : 50 : : 9 : ?

What is the equation of line whose slope is -1/2 and passes through the intersection of the lines x - y = -1 and 3x - 2y = 0?

Two numbers are 40% and 80% lesser than a third number. By how much percent is the second number to be enhanced to make it equal to the first number?

Mahesh buys 3 shirts at an average price of Rs 1250. If he buys 2 more shirts at an average price of Rs 1450 what will be the average price (in Rs) of all the 5 shirts he buys?

The average weight of 25 candles is 40 grams. If some candles of weight 50 grams each were removed, then average weight becomes 37.5 grams. How many candles of weight 50 grams each were removed? 

By selling a table for Rs. 16,870, a shopkeeper suffers a loss of Rs. 1080. His loss percentage (rounded off to one decimal place) is