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_66551 ( "Manufacturer" text, "Transmission" text, "Engine Capacity" real, "Fuel Type" text, "L/100km Urban (Cold)" real, "L/100km Extra-Urban" real, "L/100km Combined" real, "mpg-UK Urban (Cold)" real, "mpg-UK Extra-Urban" real, "mpg-UK Combined" real, "mpg-US Urban" real, "mpg-US Extra-Urban" real, "mpg-US Combined" real, "CO 2 g/km" real, "Green Rating" text )

### Question ###
What's the engine capacity when the mpg-UK urban is less than 12.2, the mpg-UK extra urban is less than 18.8 and the mpg-US turban is less than 7.2?

### Accurate SQL ###

SELECT SUM("Engine Capacity") FROM table_66551 WHERE "mpg-UK Urban (Cold)" < '12.2' AND "mpg-UK Extra-Urban" < '18.8' AND "mpg-US Urban" < '7.2'