Question 13
In Kükametsa School of Science, the number of secondary school participants in the "Kangaroo" competition was exactly one fourth greater than in the previous year. This year, the number of participants from the 11th and 12th grade was respectively 3 and 4 less than the number of participants from the 10th and 11th grade in the previous year, but the number of participants from the 10th grade this year was twice as high as the number of participants from the 12th grade last year. In the previous year, the average number of participants per grade level in Kükametsa School of Science was more than 60, but less than 65. Find all possibilities how many participants from the 10th grade could have participated in the "Kangaroo" competition this year.