00:01
The first thing we're being asked to do is to write in inequality to represent the given situation.
00:05
So it says that elena's first three test scores were 92, 85, and 96, which i noted above.
00:12
They want to figure out what does she need to get on the fourth test to maintain an average of at least 90.
00:18
So because we don't know what she got on our last test, in math, when we don't know something, we'll call it a variable.
00:23
So i'm going to call it x.
00:25
So these would be our four test scores.
00:27
So to write their inequality, don't forget to find the average of numbers, you add them all up and divide the how many numbers you had.
00:36
So in this case, we would have 92 plus 85 plus 96 plus x because she wants the average of her four test scores.
00:46
And then we're going to divide this by four.
00:48
So that's how you would find the average.
00:50
Now, we want it to be at least 90.
00:54
Well, think about what the word at least means...