What is the mean for the set of data? 6, 7, 9, 10, 11, 11 A. 11 B. 9 C. 5 D. 9.5

We will set a variable, d, to represent the day of the week that January starts on. For instance, if it started on Monday, d + 1 would be Tuesday, d + 2 would be Wednesday, etc. up to d + 6 to represent the last day of the week (in our example, Sunday). The next week would start over at d, and the month would continue. For non-leap years:
If January starts on d, February will start 31 days later. Following our pattern above, this will put it at d + 3 (28 days would be back at d; 29 would be d+1, 30 would be d+2, and 31 is at d+3). In a non-leap year, February has 28 days, so March will start at d+3 also. April will start 31 days after that, so that puts us at d+3+3=d+6. May starts 30 days after that, so d+6+2=d+8. However, since we only have 7 days in the week, this is actually back to d+1. June starts 31 days after that, so d+1+3=d+4. July starts 30 days after that, so d+4+2=d+6. August starts 31 days after that, so d+6+3=d+9, but again, we only have 7 days in our week, so this is d+2. September starts 31 days after that, so d+2+3=d+5. October starts 30 days after that, so d+5+2=d+7, which is just d. November starts 31 days after that, so d+3. December starts 30 days after that, so d+5. Remember that each one of these expressions represents a day of the week. Going back through the list (in numerical order, and listing duplicates), we have d, d, d+1, d+2, d+3, d+3, d+3, d+4, d+5, d+5, d+6 and d+6. This means we have every day of the week covered, therefore there is a Friday the 13th at least once a year (if every day of the week can begin a month, then every day of the week can happy for any number in the month).
For leap years, every month after February would change, so we have (in the order of the months) d, d+3, d+4, d, d+2, d+5, d, d+3, d+6, d+1, d+4, and d+6. We still have every day of the week represented, so there is a Friday the 13th at least once. Additionally, none of the days of the week appear more than 3 times, so there is never a year with more than 3 Friday the 13ths.

5 0

3 years ago

The towns of Franklin and Chester post their populations on signs just outside of their towns. The signs are

Andre45 [30]

Answer:

year 13

Step-by-step explanation:

franklin's population is growing by 1000 people per year(5% of 20000 is 1000) and Chester is growing by 500 per year so at year 13 franklin will be at 32000 while Chester is at 31500

4 0

3 years ago

when a car speed is 24 km/hr a journey takes 80 minutes what must the speed be for the same journey to take 60 minutes?

Mariana [72]

Answer:

32 km/ hr

Step-by-step explanation:

Given that :

Speed of car = 24km/ hr

Time taken =. 80 minutes = 80 / 60 = 1.33333 hours

The distance traveled :

Speed * time

24 km/hr * 1.333333 = 32 km

Speed required to complete 32 km. Journey in 60 minutes = 1 hour

Speed = distance / time

Speed = 32 km / 1 hour

Speed = 32 km/ hr

5 0

3 years ago