1) you would need to turn both fractions so they have a common denominator, that would be 2 2/4 and 3/4
2) then subtract : 2 2/4 - 3/4, and you would subtract numerators and the whole number, but you keep the denominator the same. However, you cannot subtract 2 and 3 in this case, so you need to change 2 2/4 to 1 5/4 (they are still equivalent)
3) 1 5/4 - 3/4 = 1 2/4, which simplified version is 1 1/2
Therefore, the answer is 1 and 1/2
The pattern is n-3, so we will start from the beginning, from 1.
7, 4, 1, -2, -5, -8, -11, -14, -17, -20, -23, -26, -29, -32, -35, -38, -41, -44.
-44 is the 18th term in the sequence.