Natalie made a mistake in the following problem.

The mistake was made in Line ___. Only input the number of the first incorrect line
Line 1
6(4) ÷ 2 − 1 + 5
Line 2
6(4) ÷ 1 + 5
Line 3
24 ÷ 1 + 5
Line 4
24 + 5
Line 5
29