I would say b hope this help ☺
Answer:
59 to 66
Step-by-step explanation:
Mean test scores = u = 74.2
Standard Deviation =
= 9.6
According to the given data, following is the range of grades:
Grade A: 85% to 100%
Grade B: 55% to 85%
Grade C: 19% to 55%
Grade D: 6% to 19%
Grade F: 0% to 6%
So, the grade D will be given to the students from 6% to 19% scores. We can convert these percentages to numerical limits using the z scores. First we need to to identify the corresponding z scores of these limits.
6% to 19% in decimal form would be 0.06 to 0.19. Corresponding z score for 0.06 is -1.56 and that for 0.19 is -0.88 (From the z table)
The formula for z score is:

For z = -1.56, we get:

For z = -0.88, we get:

Therefore, a numerical limits for a D grade would be from 59 to 66 (rounded to nearest whole numbers)
Hey mate here is your answer.
➛ 6(x-2) = 4(x+3)
➛ 6x-12 = 4x + 12
➛ 6x - 4x = 12 + 12
➛ 2x = 24
➛ x = 
⛬ x = 12
Answer:
180 miles
Step-by-step explanation:
The are moving towards each other at 50 mph and 40 mph which is the same as 90 mph. They are moving 90 mph closer to each other every hour so in 2 hours it would be 180 miles.