Answer:
a) The expected number of questions that are answered correctly by both A and B = 11 (7 + 4).
b) The Variance of the number of questions that are answered correctly by either A or B = 2.25.
Step-by-step explanation:
Number of questions in the examination = 10
Probability of A's answer being correct = 0.7
Probability of B's answer being correct = 0.4
The expected number of questions that are answered correctly by both A and B:
Probability of Expected
Correct Answer Value Variance
A 0.7 7 (0.7 * 10) 2.25
B 0.4 4 (0.4 * 10) 2.25
Total expected value = 11
Mean = 5.5 2.25
Answer:
The wagon can hold 32 newspapers
Step-by-step explanation:
2.8y + 6 + 0.2y = 5y – 14
Simplify the left side:
3y +6 = 5y-14
Subtract 3y from both sides:
6 = 2y -14
Add 14 to each side:
2y =20
Divide both sides by 2:
y = 20 / 2
y = 10
Answer:
60m/s
Step-by-step explanation:
velocity of the while moving is 30 m/s and it becomes 90 m/s after speeding up at constant rate. so the average velocity of the journey is
[90+30] /2
=60 m/s
One possible inequality would be
1999-x<0.
If you subtract any year after he stepped down from 1999, the year he stepped down, the result will be a negative number.