you did fine
the only thing I would object to is your running of the equal sign across the page.
here is how it should be presented:
v1 + 2v2 = 9000
v1 + 2(7500-2v1) = 900
v1 + 15000 - 4v1 = 9000
7500 = 3v1
v1 = 3500
etc.
each line should contain only one equal sign, it makes it so much easier to read.
Together, two printers can print 7500 lines if the first printer prints for 2 minutes and the second prints for 1 minute. If the first printer prints for 1 minutes and the second prints for 2 minutes, they can print 9000 lines together. Find the number of lines per minute that each printer prints.
My answer:
let first print speed: v1 (limes/min)
second print speed : v2 (lines/min)
2v1+v2 = 7500 lines =>v2 = 7500 - 2v1
v1 + 2v2 = 9000 lines
=> v1 + 2(7500-2v1) = v1 + 15000 - 4v1 = 9000
=> 3v1 = 15000 - 9000 = 2000
=>v1 = 2000 lines/min
v2 = 7500-2*v1 = 7500 - 2*2000 = 3500 lines/min
answer:
first print speed: 2000 lines/min
second print speed: 3500 lines/min
Check please, I'm not too good at word problems!
1 answer