What is the mean of the numbers 45, 55, 65, 75?

What is the mean of the numbers 45, 55, 65, 75?

• A. 50
• B. 60
• C. 65
• D. 70

Answer: (B)

Mean is the average value, found by adding all the numbers together and dividing by how many numbers there are. For 45, 55, 65, and 75, add them: 45 + 55 + 65 + 75 = 240. There are four numbers, so 240 divided by 4 gives 60. So the mean is 60. The other options would require a different total (for example, a total of 200 would give 50, 260 would give 65, and 280 would give 70), but with these four values the total is 240, yielding 60.

Mean is the average value, found by adding all the numbers together and dividing by how many numbers there are. For 45, 55, 65, and 75, add them: 45 + 55 + 65 + 75 = 240. There are four numbers, so 240 divided by 4 gives 60. So the mean is 60. The other options would require a different total (for example, a total of 200 would give 50, 260 would give 65, and 280 would give 70), but with these four values the total is 240, yielding 60.