What minus 1 equals 20?

Here we will show you how to calculate "What minus 1 equals 20?" using simple algebra.
For the sentence, "What minus 1 equals 20?", we can make it into an algebra equation as follows:
X - 1 = 20
Then, we solve for X. To solve for X, add 1 to both sides:
X - 1 + 1 = 20 + 1
Which makes:
X = 21
Thus, the answer to "What minus 1 equals 20?" is 21 as illustrated below:
21 - 1 = 20