Solve :

3(2u + v) = 7 uv

3(u + 3v) = 11 uv

Use method of cross-multiplication to solve :

(i) 2x + y = 8 and 3x - 2y = 5

(ii) x + 4y = 3 and 2x + 9y = 5

Seven times a two digit number is equal to four times the number obtained by reversing the order of digits. Find the number, if the difference between its digits is 3.