Answer: Model A: 6, Model B: 3
Step-by-step explanation:
Model A can pring 50 books per day so since you have 6 of those, the Model A printing presses would pring 300 per day (50 x 6). If you have 6 of the Model A printing presses, that means you have 3 Model B printing presses because there is a total of 9 printing presses. Therefore, you would multiply 3 by 30 which is 90 because the Model B ones can pring 30 per day.
390 (books total) = (50 x 6) + (30 x 3)
390 = 300 + 90
Answer: there are 6 model A printing presses.
there are 3 model B printing presses.
Step-by-step explanation:
Let x represent the number of Model A printing presses.
Let y represent the number of Model B printing presses.
The company own 9 total printing presses. This means that
x + y = 9
Model A which can print 50 books per day and Model B which can print 30 books per day. The company own 9 total printing presses and this allows them to print 390 books per day. It means that
50x + 30y = 390 - - - - - - - - - - - -1
Substituting x = 9 - y into equation 1, it becomes
50(9 - y) + 30y = 390
450 - 50y + 30y = 390
- 50y + 30y = 390 - 450
- 20y = - 60
y = - 60/ - 20
y = 3
x = 9 - y = 9 - 3
x = 6
