In a class of 30 students, what is 40% of the total number of students?

To determine 40% of a class of 30 students, you can convert the percentage into a decimal and then multiply it by the total number of students.

First, convert 40% to a decimal by dividing 40 by 100, which gives you 0.40. Next, multiply this decimal by the total number of students:

0.40 x 30 = 12.

Therefore, 40% of 30 students is 12. This means that the correct answer is the option that represents this value. Understanding the calculation helps reinforce concepts of percentage and multiplication in relation to real-life scenarios, such as determining parts of a whole in a classroom setting.