1、 The sum of the reciprocal of two natural numbers is 11 out of 28. What are the two natural numbers? 2、 The reciprocal sum of the three prime numbers is 311 / 1001. What are the three prime numbers?

1、 The sum of the reciprocal of two natural numbers is 11 out of 28. What are the two natural numbers? 2、 The reciprocal sum of the three prime numbers is 311 / 1001. What are the three prime numbers?

1/A + 1/B =(A+B)/A*B
So decompose the denominator and find the right combination
1. 4 and 7
2、11,13,7