Understanding Averages and Solving Word Problems

This video tutorial focuses on understanding and calculating averages through various examples. It begins with an introduction to the concept of averages and basic formulas. The tutorial then presents several problems, each demonstrating how to calculate averages in different scenarios, such as exam scores and sets of numbers. The video concludes with a problem involving variables, illustrating the effect of adding a number to a list on the average.

What is the formula for calculating the average of a set of numbers?

• Sum of numbers divided by the number of numbers

• Product of numbers divided by the number of numbers

• Sum of numbers multiplied by the number of numbers

• Product of numbers multiplied by the number of numbers

How do you express the sum of eight numbers using their average?

• Average of eight numbers minus 8

• Average of eight numbers plus 8

• Average of eight numbers divided by 8

• Average of eight numbers times 8

If the average of four exams is 82, and the fifth exam score is 97, what is the new average?

• 87

• 86

• 85

• 84

In the problem involving Lisa's chemistry exams, what is the sum of the first four exam scores if their average is 82?

• 336

• 328

• 344

• 320

Gerald's average score for nine tests was 96. If two test scores sum to 178, what is the average of the other seven tests?

• 98

• 97

• 96

• 95

What is the sum of all nine test scores if the average is 96?

• 880

• 872

• 864

• 888

If the average of eight numbers is 46 and the average of three of these is 51, what is the average of the other five numbers?

• 45

• 44

• 43

• 42

What is the average of all seven numbers in set X if the average of the first two numbers is 79 and the sum of the last five numbers is 290?

• 65

• 62

• 64

• 63

If the average of three numbers is 51, what is their total sum?

• 150

• 159

• 153

• 156

If the average of five numbers is y, and adding another number makes the average y + 3, what is the value of the added number?

• y + 18

• y + 15

• y + 21

• y + 24