it will take 18 days for cameron to complete a certain task alone . he worked for 9 days before she was joined by sandra . both of them completed the remaining task in 3 and half days . how many days will it take both of them to complete the entire job ?
explanation : cameron and sandra completed half work in 3.5 days = > they can complete whole work in 7 days answer : option b
divide(add(3, divide(const_1, const_2)), divide(9, 18))