Activity 1: Share your screen. (We will discuss the sums together)
https://www.liveworksheets.com/worksheets/en/Math/Averages/Averages_lz1503770en
Averages: Finding an Unknown Value
Example:
The average of four numbers is 15.
Three of the numbers are 9, 12 and 19. Find the fourth number.
Step 1: Add the numbers you have been given.
9+12+19= 40
Step 2: Multiply
15 x 4 = 60
Step 3: Subtract
Unknown value: 60-40= 20
Sunil wants to earn an 88% in her Chemistry class. She has one quiz left to take. On the first 5 quizzes, she received a 74%, 92%, 83%, 98%, 100%. What must she score on the 5th quiz to get the 88% she wants?
2-3.
4. After working 5 days, an employee earned an average of $520. On four of those days, he earned $600, $345, $440 and $500. How much did he earn on the fifth day?
Share
5. Kelly collected an average of 50 stamps after 4 weeks. In week one she collected 60 stamps and in week 2 she only collected two-thirds of this amount. In week 3, she collected 80 stamps. How many stamps did she collect in week 4?
6. The mean weight of five complete computer stations is 167.2 pounds. The weights of four of the computer stations are 158.4 pounds, 162.8 pounds, 165 pounds, and 178.2 pounds respectively. What is the weight of the fifth computer station?
7.The mean of four numbers is 71.5. If three of the numbers are 58, 76, and 88, what is the value of the fourth number?
Comments
Post a Comment