1.13 find the resultant force of forces that act along a line

This is just maths:
 You take the smaller one away from the bigger on and bam :)
Note that this is only for ones along a straight lines, ones at right angles are slightly trickier.

1.








2.







Answers:
1. 16 - 4 = 12N right
2. 60-20 = 40N East