I can't help really, in terms of showing steps because I haven't been taught this yet..
but using an online calculator... I found that x ≤ 20.
Graph:
|-----------------|-----------------|
-20 0 20
4:5 is the same as 4x:5x where 4x is compound A and 5x is compound B.
---
Solve for "x":
If amount of compound A is 4x = 477
x = 477/4
Then amt of compound B is 5x = 5(477/4) = 596.25 ml
Answer: 12 miles per hour.
Step-by-step explanation:
Given: Distance travelled = 
Time taken =
hour
Unite rate = speed
The formula for speed is given by:-

So, unit rate = 

Hence, unit rate = 12 miles per hour.
3 + 126 - 4• 526 - (4x)
3 + 126 -2104 -4x
-4x -1975