One printing press can print an order of advertising brochures in 8.5 hours. Another press can do the same job in 9.5 hours. How long will it take if both presses are used? Hint. You may find that multiplying on both sides of the equation by 110th will clear the decimals. So the easiest way I can tell you to do this is to think about job per time. So if we have one job, we can do it in 8.5 hours by one of the presses. Another press does one job in 9.5. Well, we want to think about if they're working together. So if they're working together, we're going to add them and that's going to be one job in X amount of hours. Now, our book does things like it says X / 8.5 + X / 9.5 equal 1. And this is true, This is a rate per time. But I think that for a lot of students just understanding one job in this amount of time and another job in this amount of time. So one job and how much time? If they're working together, Both methods work. You can choose which one you like. So the scent about multiplying by 110th. If I multiply everything through by 110th, I get 1 / 85, one over 95 equaling 1 / 10 X. Or if you did it over here, you'd get X / 85 + X / 95 equaling 110th. So the common denominator, we can see that there's a 5 in common. I don't know what else is in common. So I'm going to multiply the 10. One is going to be 2 * 585. Five goes into eight one whole time with three leftover. So five goes into 35 seven times. Five goes into 95.5 goes into nine once, with four leftover, five goes into 45 nine times. So our common denominator here is going to be 5 * 17 * 19 * 2 * X. Now, if I multiply the common denominator through by everything, and I'm not going to multiply that number out because things are going to cancel here in just a second. I'm going to take that common denominator and multiply it by that 185th which was 5 * 17. I'm going to take that common denominator again and multiply it by that 1 / 95 which was 5 * 19. And then I'm going to take that common denominator and multiply it by the one over 10X which was 1 / 2 * 5 X. So now if we look at things, this five and that five are going to cancel and the 17 and that 17 are going to cancel. That's going to leave us 19 * 2 X SO38X on this next one, the fives are going to cancel and the 19 is going to cancel, leaving me 17 * 2 X times one. So that's going to give me 34 X and over here on the right side of the equation, the two and the five and the X is going to cancel 17 * 19. I don't know off the top of my head, 17 * 19 three carry 6-7 and 691-323-2319 times seven. That seems right. So then where's my pen 323? So then 38 and 34 are going to give me 6072 X equaling 323, so 323 divided by 72 which it tells me oh it says write an integer or fraction. So we're going to leave it as 300 and 2370 seconds.