From 1 to 100 0 is repeated for 11 times 1 is repeated for 21 times 3 to 9 repeats for 20 times so there are 20 numbers that contain 5 in it 5, 15, 25, 35, 45, 50, 51 to 59, 65, 75, 85, 95
Suppose rate of each typist is R So rate of two typist will be 2R time = 2mins work = 2pages using : Rate * Time = Work ,we have: 2R * 2 = 2 => R = 0.5 pages/min
Suppose x number of typist are required to finish 18pages in 6mins So, rate of R typist will be xR Time = 6mins work = 18pages Using Rate*time= work we have
xR * 6 = 18 => xR = 3 we know that R =0.5 => x = 6