Answer:
357 minutes
Step-by-step explanation:
I subtracted 9 cents/minute from the 23 cents/minute to get 14 cents to get the difference between the two per minute charges. I then divided the monthly cost of $49.95 by .14 to get 356.79... So if you used 357 minutes in a month, the second plan would be 3 cents cheaper at $82.08 (.09 x 357= 32.13 + 49.95), vs. the first plan costing $82.11 (.23 x 357). At 356 minutes the first plan would still be cheaper.
Answer:
1/4: 1s/4
7/8: 7x/s
Step-by-step explanation:
Given:
mean = 64
standard deviation = 6
sample size = 50
Standard error of the sample mean = standard deviation / √sample size
Standard error = 6 / √50 = 6/7.07 = 0.85