There are many ways to do this depending on the property you have to use:
If you use the distributive property, you need to distribute 3/4 to -10 and 2/5. Distribute means you will multiply it so your resulting equation will be this:

Before you can add, you need to first make them like terms because you cannot add unlike fractions. Get the LCD and form your new equation:

Now you can just add them together to get:

and then simplify your fraction:

or -
The whole fraction becomes negative because when you divide integers and of them is negative, the final answer will be negative.
Answer:
Provide the statements please
Step-by-step explanation:
The cost of 8 shirts is 120$
I believe your answer will be 2.4 because 2 cannot be rounded up by 3 and 3 can be rounded up to 4 by 6
255 l ------ 340km
x l -------- 100km
100*255=340x
25500=340x
x=75 litres