Answer:
8x - 4
Step-by-step explanation:
8x - 4
C.) 3:5 = 12:20
It is this because you can divide them evenly into each other. 3*4 is 12 and if you do 5*4 it is 20. Boo yeah
Answer:
90 g of water should be added and he will make 900 g of solution.
Step-by-step explanation:
Let x g be the amount of salt Ilya add to 810g of water to make 10% solution. Then 810+x g is the amount of new solution. Thus,
810+x - 100%,
x - 10%.
Mathematically,

So 90 g of water should be added and he will make 810+90=900 g of solution.
60 miles because 2160 divided by 36 = 60