Three identical numbers are arranged into three simple formulas, and the results must be equal to 30, Are three identical numbers, 30 + 30-30 = 30 * 30 / 30 = 30 / 30 * 30 = 30

Three identical numbers are arranged into three simple formulas, and the results must be equal to 30, Are three identical numbers, 30 + 30-30 = 30 * 30 / 30 = 30 / 30 * 30 = 30

The numbers are different, and there are many cases that can be made up
1 + 1 * 29 = 30
1 * 1 + 29 = 30
1 / 1 + 29 = 30
1 * (1 + 29) = 30
The landlord added that if there are three identical numbers, then only 30 can form several groups
30 + 30 - 30 = 30
30 - 30 + 30 = 30
30 * 30 / 30 = 30
(30 /30)* 30 = 30
30 * (30/30) = 30
30 / (30/30) = 30
For a certain number a, three same numbers are added, subtracted, multiplied and divided, and considering the use of brackets to enhance the operation priority, there are more than 20 combinations that can be obtained. The different values that can be obtained are 3a, a, 2A ^ 2, a ^ 2 + A, a ^ 2-A, A-A ^ 2, a ^ 3, a + 1, A-1, 1-A, 1 / A, 2, 0, 1 / 2, etc. there are more than ten limited values, and only the operation result a appears more than three times. To make the other results choose two are equal to 30, there is no solution
Therefore, if the result is equal to 30, a which can list three or more formulas can only be equal to 30