A school assembly had 40 students in attendance, and 90% of them were first-graders. How many first-graders were at the assembly?

Answer 1

To find the number of first-graders at the assembly, we can calculate 90% of the total number of students present, which is 40.

First, we convert the percentage to a decimal: \[ 90% = 0.90 \]

Next, we multiply this decimal by the total number of students: \[ 0.90 \times 40 = 36 \]

Therefore, the number of first-graders at the assembly is \(\boxed{36}\).