Answer:
a. 47
b. 87
c. 127
Step-by-step explanation:
Assume a total of 4 exams ( first 3 plus a final)
Let final score be X,
Hence, average score = (85 + 71 + 77 + x) / 4 = (233 + x) / 4
a) to get a C, the average score must be 70
70 = (233 + x) / 4
(233 + x) = 70 (4) = 280
x = 280 - 233 = 47 (Ans)
b) to get a B, the average score must be 80
80 = (233 + x) / 4
(233 + x) = 80 (4) = 320
x = 320 - 233 = 87 (Ans)
c) to get a A, the average score must be 90
90 = (233 + x) / 4
(233 + x) = 90 (4) = 360
x = 360 - 233 = 127 (Ans)
Answer: 1/70
Step-by-step explanation:
This is a question that can also be interpreted as what is the probability of having the first number of a phone number to be 8 and the last number of the phone number to also be 8. This answer gives the fraction of the phone numbers that starts with 8 and end with 8.
Since three numbers (0,1,2) cannot start a phone number and we are left to pick from 7 numbers,
then the probability of figure "8" starting phone number = 1/7
Since all 10 numbers can possibly end a phone number,
then the probability of having figure "8" as the last digit of a phone number = 1/10
Hence probability of having "8" as the first and last digit of a phone number = fraction of total telephone numbers that begin with digit 8 and end with digit 8 = 1/7 × 1/10 = 1/70.
Answer:
look down there
Step-by-step explanation:
First ball:
Probability of drawing a white ball is 5/8
Probability of drawing a black ball is 3/8
Second ball:
This depends on the first ball drawn, lets say you drew a white ball initially, 4 white balls are left out of 7 balls in total. The probability of a white ball in the second pick is 4/7.
Total probability of drawing two white balls is 5/8*4/7 (since they are independent events).
If you picked a black ball initially, picking another black ball would have a probability of 2/7, on similar grounds , total prob for 2 blacks would be 3/8*2/7.
The probability that you pick 2 balls of same color is (5/14 + 3/28) = 13/28. (Since they are mutually exclusive events)
If you were to draw the cosx and sinx graph there will be infinite solutions at their interceptions which are the multiple of pi/4
Answer:
2x as much
Step-by-step explanation:
First write as an equation:
<u>3000/32*3.75 =</u>
3000/16*3.75
Then that equals:
0.5
So that means her mom's car would be half as efficent as the new one
