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.
** x + 5 = 7
x = 2
** x + 5 = 9
x = 4
{2,4}
There are 12 student(s) in the group, because there is 12 one-third part(s) in 4 while jars
Answer:
If you substitute (-1,2) meaning x and y
2=3(-1)-2
2=-3-2
2= -1
Step-by-step explanation:
he's incorrect since the solution does not equal 2 on both sides
Answer and explanation:
We know that this is in slope-intercept form. ( y = mx + b )
1/2 would be the slope (you would use this to graph the next point)
-4 would by your y-intercept (where the line crosses the x-axis)
With this information you could graph any point using the slope given, starting at -4 (x-axis) going down or up.