To find the total number of sixth-grade students surveyed, we need to add up the frequencies for the subjects for the sixth grade from the provided data:
- Sixth grade Math: 53
- Sixth grade English: 47
- Sixth grade Science: 42
Now let's do the calculation:
Total sixth-grade students = 53 + 47 + 42 = 142
So, the total number of sixth-grade students that were surveyed is 142.