Answer:
20 Yellow Counters
Step-by-step explanation:
You can see the clues with how the ratio changes.
To change from (1:4) => (5:1) is not because any were taken away from the value that is the Yellow counters, it is purely because the amount added to the blue counters was so large that they simply simplified the ratio.
The real value of the ratio if reverted back to it's original state would be:
=> (20:4)
95 blue counters is equivalent to 19 in the ratio. We know this because it increased from 1 to 20.
95/19 => 5
Each Ratio in the original one presented is equal to 5.
5 * 4 = 20 Yellow Counters