Respuesta :

50 point because 4 x 50 + 150 = 350 - 300 = 50.
the expression:
-50 + 150 -250+50+50+50+50

step 1:
100-250+50+50+50+50

step 2:
-150+50+50+50+50

step 3:
-100+50+50+50

step 4:
-50+50+50

step 5:
0+50

Answer:
50