Adding odd numbers will only give you an even sum if the amount of numbers you added is an even number.
For example,
25 is an odd number. If you add 25, 2 times (2 is an even number) you will get 50 (an even number). If you add 25, 4 times (4 is an even number) you will get 100 (still, an even number)
However, if you add 25, 3 times (an odd number) you will get 75 (an odd number). If you add 25, 5 times (an odd number) you will get 125 (still an odd number).
Hopefully, that helped (: Sorry if I confused you lol
By Newton's second law, the net force on the object is
∑ F = 10.0 N + F = (7.0 kg) (1.0 m/s²)
where F is the unknown force. Since the object is accelerating to the east, F must be acting in the same or opposite direction as the known force that is also directed eastward. Solve for F :
10.0 N + F = 7.0 N
⇒ F = - 3.0 N
which is to say, F has magnitude 3.0 N and points toward the west.
