Answer:
The number of machines to complete job in 2 hours is 6.
Step-by-step explanation:
Using the relation of the rate of each one machine and knowing that adding up both rates.

Rate R =
'x' is the job
Rate S =
'x' is the job
So, using the equation of rates

Rate total is going to be a job in 2 hours so = 
<em>adding up</em>
<em>factoring the x</em>
<em>simplifying</em>
x= 
x= 6
What you need to do is give these problems a common denominator. Which makes 3/21 and14/21 respectively. Logically, you need to walk 4/21 of the trail. This can’t be simplified further.
Step 1. Type it into a Google search box or calculator. (You need to use a calculator anyway.) The result is
3177 4/9.
If you're doing this according to the Order of Operations, you do the multiplication and division left to right. This means the first calculation you do is
255/6 = 42.5
Next, you multiply by 672
42.5*672 = 28560
Then divide by 9
28560/9 = 3173 3/9
You continue by doing the division
37/9 = 4 1/9
And finish by adding the two results
3173 3/9 + 4 1/9 =
3174 4/9_____
If you're doing this by hand, you can recognize the first term as the product of two fractions, so is the product of numerators divided by the product of denominators.
(255*672)/(6*9)
Using your knowledge of divisibility rules, you can do the division 672/6 to simplify this to
(255*112)/9
Now, the first term and the second term have the same denominator, so you can add the numerators before you do the division.
(255*112 + 37)/9 = (28560 + 37)/9 = 28597/9
You end up having to do only two simple divisions, rather than 3 of them.
28597/9 = 3177 4/9
9) They traveled 31.9 hours over the 3-day trip.
10.9 + 8.6 + 12.4 = 31.9
10) She does not have enough money. She has $12, but everything she wants to purchase would cost $12.39.
Large drink = 1.79
Turkey sandwich = 4.85
1.79 + 4.85 = 6.64
6.64 + 5.75 = 12.39