My Formula Field is producing errors & what is the best way to express...

My Formula Field is producing errors & what is the best way to express...

When I use the formula field and input the following: (y_o_main_pts  +  y_o_comm_pts  +  y_o_demo_pts + y_o_sni_pts) it saves it this way: (y_o_main_pts  +  y_o_comm_pts  +  y_o_demo_pts) + y_o_sni_pts

Also I would like to know how to write the foolwong expression:
125 - (y_o_main_pts  +  y_o_comm_pts  +  y_o_demo_pts + y_o_sni_pts) = whatever the sum totals