A phone company has two long distance calling plans. The first plan is $25 per month
for unlimited long distance calling. The second
plan is $10 per month plus $0.05 per minute
of long distance calling. After how many
minutes of long distance calls will it be cheaper
for a customer to purchase the first plan?

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.

Sum of the interior angles of a pentagon