The best way to put them into a number line is to make sure that they've all got the same denominator, which in this case, will be 24, as this is the lowest common multiple of 3,4 and 8. You will then need to multiply these fractions accordingly. The first one (1/4) will need to be multiplied by 6 to get a denominator of 24, so this will then give you a result of 6/24. The second one (2/3), will need to be multiplied by 8, which will then give you a result of 16/24. The third one (3/4)will also need to be multiplied by 6, giving you 18/24. The final one (6/8) will need to be multiplied by 3, giving you 18/24. You will then need to put these in order, which will be- 1/4, 2/3, 3/4, and 6/8.
The alternative method is to turn these into decimals- 1/4 is equivalent to 25%, which is equal to 0.25. 2/3 is equivalent to 66.66%, which is equivalent to 0.66. 3/4 is equivalent to 75%, which is equal to 0.75. 6/8 is also equivalent to 75%, which is equal to 0.75, you can then easily line them up this way.
Hope this has been able to help you
        
             
        
        
        
C, I’m pretty sure
Why do I have to write 20 words for this? This is why I’m rambling.
        
             
        
        
        
Answer:
He can go 10.78 miles
Step-by-step explanation:
This problem can be solve by creating a proportion, knowing that 15.4 miles is to one gallon the same as "x" miles (our unknown) is to 0.7 gallons. This can be set in math terms as the equation that relates these two ratios of miles per gallon:

and to solve for the unknown number of mile, we multiply both sides of the equation by "0.7 gallon" in order to isolate our unknown:

 
        
             
        
        
        
Answer:
Step-by-step explanation:
For this sort of problem, there can be an infinite number of answers. 
It can be convenient to choose one of the simpler answers by looking at the operations that are performed on the variable. Here, you have ...
- 2 multiplies it
- 4 is added to the product
- the square root is taken
- 8 is divided by that root
You can work from the bottom up and define the outer function (f(x)) to be any of these operations. In our answer above, we have elected to include the "square root" and the "8 divided by that root" in our definition of f. 
Then our function g takes care of the other operations.