The error rate has decreased after changing the painting process.
<u>Step-by-step explanation:</u>
Abdulla knows that 20 percent of the parts have an error in their painting. After suggesting changes in painting process, he wants to know whether the error rate has changed.
Number of parts in the random sample=400400400
Number of parts that had an error=606060
We have to determine what percentage of 400400400 is 606060

After changing the painting process 0.15% of parts have error.
The previous percentage was 20.Hence the error rate has clearly changed.
So it starts with 12 in the bacterial population. After 1 hour, 6 are added. After another hour passed, 9 are added. 12/1, 18/6, 27/9.
Answer:
(5x = 2 = 3 +8a
Step-by-step explanation:
100 tickets were sold.
The total amount of the tickets sold is = 5 * 100 = $500.
First prize given = $100
Second prize worth = $20 * 5 = $100
Total worth of prize + $100 + $100 = $200.
Net amount of tickets sold = $500 - $200 = $300
Expected price of each ticket sold = $300/100 = 3.
Therefore, the real price of each ticket sold is $3.