6.5 Applying Averages

Obj: To calculate average and Obj: To calculate average and solve problems with averagesolve problems with average

Find Average = Sum

# of items

Example 1

Find the average:Find the average:

95, 95, 95, 7595, 95, 95, 75

95 95 95 4/360 = 90%95 4/360 = 90% 9595 + 75+ 75 360360

Midpoints

A ____________ BA ____________ B

½ way or midpoint Midpoint= A+B

2

Because you have

2 points.

Example 2

Find the midpoint

< >< >14-6

Midpoint = 8 = 4

2

Example 3

Cody wants a 90 for the marking period. If his grades Cody wants a 90 for the marking period. If his grades are 75, 85 and 100- what must he get on the 4are 75, 85 and 100- what must he get on the 4thth test? test?

Let X = 4Let X = 4thth Test Test

Average= Average= Sum Sum

Number 4 [ 90= Number 4 [ 90= 75+85+100+X75+85+100+X] 4] 4

44

360360==260X260X

200 260 200 260 90 = 260+X

90x4 4X=100