Question 322915
let the old printer's speed be x checks 
1/x of the check it does it 1 minute
..
new printer will print at 3x checks 
1/3x checks it prints in 1 minute
..
both print in 6 minutes
So 1/6 of the job they do in 1 minute
..
1/x + 1/3x = 1/6
3+1 /3x= 1/6
6*4=3x
3x=24 
x= 8 checks by the old printer