Составьте 10 правильных дробей из чисел 2,5,7,13,и21 числа можно использовать несколько раз

Sure! Here are 10 proper fractions that can be formed using the numbers 2, 5, 7, 13, and 21:

1. 2/5
2. 7/13
3. 13/21
4. 5/7
5. 21/2
6. 7/2
7. 13/5
8. 5/13
9. 21/7
10. 2/21

Please note that these fractions are simplified to their lowest terms.