Answer:
b. $28
Step-by-step explanation:
We have these following probabilities:
0.4 = 40% probability of $40
0.2 = 20% probability of $30
0.2 = 20% probability of $20
0.2 = 20% probability of $10
The expected value is:
We multiply each value by its probability. So
So the correct answer is:
b. $28
The apprentice needs 6.25 hours to complete the job using the brush
<h3><u>Solution:</u></h3>Given, A master painter can paint 110 square yards of surface area with a roller in 1 hour
We know that 1 yard = 3 feet
While his apprentice can paint 85 square feet of surface area per hour with a brush
Together they are painting a building with a surface area of 5100 square feet.
After painting for hours , the master painter lets the apprentice Finish the job.
Now, they worked for hours
Then, area painted = area painted by master + area painted by apprentice
Now, the remaining area to be painted = total area – painted area
Area to be painted = 5100 – 4568.75 = 531.25
So, apprentice has to paint 531.25 square feet alone.
Hence, the apprentice needs 6.25 hours to complete the job