If 4x+5y=83 and $$ \ {3x\over2y}={21\over22}$$then what is the value of y-x ?

The number of mainas and parrots in an aviary is in the ratio of (4x + 5) : 4x. If 25 mainas and 10 parrots are added to the aviary, then, the ratio would change to 5: 3. How many mainas are there in the aviary at initial?

For what value of m will the system of equations 18x-72y+13=0 and 7x-my-17=0 have no solution?

A number divided by 13 leaves a remainder 1 and if the quotient, thus obtained, is divided by 5, we get a remainder of 3. What will be the remainder if the number is divided by 65?

The height of a wall is six times its width and the length of the wall is seven times its height. If volume of the wall be 16128 cube m, its width is 

Find the value of (cosA - sinA)² + (cosA + sinA)²   -

The average weight of P, Q and R is 93 kg. If the average weight of P and Q is 89 kg and that of Q and R average weight is 96.5 kg ,  then the weight (in kg) of Q is____.

Directions: Study the following table carefully to answer the questions that follow .
Number of soldiers ( in thousands ) joining five different forces during six different.

What was the ratio of the number of soldiers joining Army in the year 2008 to the number of soldiers joining Army in the year 2006?