Adding 10s
130 + 20 =
150
230 - 30 =
200
500 + 200 =
700
600 - 300 =
300
200 + _____ = 300
100
149 + 40 =
189
375 - 40 =
335
450 + 100 =
550
430 - 100 =
330
600 - ______ = 400
200
316 + 60 =
376
887 - 20 =
857
420 + 300 =
720
550 - 400 =
150
460 + _____ = 500
40
580 + 30 =
610
330 - 50 =
280
224 + 600 =
824
635 - 400 =
235
680 - ______ = 660
20
895 + 60 =
955
625 - 40 =
585
710 + 200 =
910
987 - 400 =
587
______ = 540 - 300
240