Final answer:
To find the total number of students at the school, divide the number of students playing at least one sport (129) by the percentage of students that represent this group in decimal form (0.30), resulting in a total of 430 students.
Step-by-step explanation:
The question asks us to find the total number of students at a school given that 129 students, which corresponds to 30% of the total, play at least one sport. To find the total number of students, we divide the number of students playing sports by the percentage (in decimal form) that represents them. Since 30% is equivalent to 0.30 in decimal form, the calculation to find the total number of students (T) is as follows:
T = 129 ÷ 0.30
By performing this division, we get:
T = 430
Therefore, the total number of students at the school is 430.