(x + 20) : 99 = (1004 + 1) x 2/99
=> 99x + 1980 = 1005 x 2/99
=> 99x = 99495/2 - 1980
=> 99x = 95535/2
=> x = 965/2
b. \(\frac{x+140}{x}\) + 260 = 21 + 65 x 4
=> \(\frac{x+140}{x}\)= 21 + 260 - 260
=> \(\frac{x+140}{x}\)= 21
=> 21x = x + 140
=> 20x = 140
=> x = 7