Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_30 ( _inches VARCHAR, skin_depth INTEGER, resistivity__10_−6_ohm_inches_ VARCHAR, relative_permeability VARCHAR )

### Question ###
What is the sum of skin depth with a resistivity of 1.12 and a relative permeability larger than 1?

### Accurate SQL ###

SELECT SUM(skin_depth), _inches FROM table_name_30 WHERE resistivity__10_−6_ohm_inches_ = 1.12 AND relative_permeability > 1