Mrs. Kemp had 20 students in her kindergarten class at the beginning of the year. She had 23 students at the end of the year.

What was the percent of increase in the number of students from the beginning of the year to the end of the year?

15%

Step-by-step explanation:

23 is 115% of 20 therefore, we can know that 23 is a 15% increase from 20.

13%

Step-by-step explanation:

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents