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:




Step-by-step explanation:
Given
See attachment for proper format of table
--- Sample
A = Supplier 1
B = Conforms to specification
Solving (a): P(A)
Here, we only consider data in sample 1 row.
In this row:
and 
So, we have:



P(A) is then calculated as:


Solving (b): P(B)
Here, we only consider data in the Yes column.
In this column:
and 
So, we have:



P(B) is then calculated as:


Solving (c): P(A n B)
Here, we only consider the similar cell in the yes column and sample 1 row.
This cell is: [Supplier 1][Yes]
And it is represented with; n(A n B)
So, we have:

The probability is then calculated as:


Solving (d): P(A u B)
This is calculated as:

This gives:

Take LCM


Answer:
100°
Step-by-step explanation:
360 degrees around a point.
140 + 120 = 260
360 - 260 = 100