Answer:
Range is 18.
Step-by-step explanation:
Range can be calculated by subtracting the smallest value of the data set from the largest value of the data set.
The values are:
13, 17, 18, 15, 12, 21, 10, 6, 8, 11, 3
Largest Value in this data set: 21
Smallest Value in this data set: 3
Range = Largest Value - Smallest Value
Range = 21 - 3
Range = 18
You can solve this one by adding their rates, but you have to invert the numbers they give you to find the rate. Rate is measured in something per unit of time, and "per" indicates division. So the rates are: 1/3 of an hour (Sally) and 1/6 of an hour (Steve). So add the rates: 1/3 + 1/6 = 1/2. (1/3 is 2/6, and 2/6 + 1/6 = 3/6). Since their combined rate is 1/2 of a room in one hour, it takes them two hours to paint the room.
This answer makes sense: It takes Sally three hours by herself; with Steve's help, she's faster, but not THAT much faster, because he's pretty slow. You can often spot-check word problem answers like this by giving it a common sense once-over. If we came up with four hours, that would clearly be wrong: it should take her LONGER if she's getting help.
Answer: C. A line that rises from left to right has a positive slope.
Step-by-step explanation: A. has a slope of 0, B. has an undefined slope, and D. is supposed to go left to right not right to left.
