average of 6 numbers is 19.A seventh number is added and the new average is 20.What is the seventh number?
6*19 + x = 7*20
x = 26
or, you could notice that if the average is raised by 1, then 1 must be added to each of the other 6 numbers, so now you have 6+20=26 more.
To find the seventh number, we need to understand how averages work and use a little algebra.
Let's start by finding the total sum of the six numbers. We know that the average of these six numbers is 19, so the sum of the six numbers must be 6 times 19, which is 114.
Now, a seventh number is added, and the new average is 20. To find the sum of all seven numbers, we can multiply the new average (20) by the total number of numbers (7). This gives us a new sum of 140.
Finally, we can subtract the sum of the original six numbers (114) from the new sum (140) to find the seventh number.
Seventh number = New sum - Sum of six numbers
Seventh number = 140 - 114
Seventh number = 26
Therefore, the seventh number is 26.