Final answer:
To solve the percent problem with an unknown percentage, set up a proportion. In this case, 5 letters is 50% of 10 letters.
Step-by-step explanation:
A percent is a way of expressing a fractional amount of something using a whole divided into 100 parts. To solve the percent problem with an unknown percentage, you can set up a proportion. In this case, you want to find what percent of 10 letters is 5 letters. You can set up the proportion as:
5/10 = x/100
Now, you can cross multiply and solve for x:
5 * 100 = 10 * x
500 = 10x
x = 500/10
x = 50
Therefore, 5 letters is 50% of 10 letters.