Adding and Subtracting

Adding without composing

100

10+15

25

200

25+31

56

300

135+31

166

400

264+221

485

500

315+463

778

Adding with composing

100

25+45

70

200

75+67

142

300

245+67

312

400

315+596

911

500

754+365

1,119

Subtracting without decomposing

100

25-15

10

200

85-23

62

300

155-43

112

400

325-212

113

500

789-345

444

Subtracting with decomposing

100

35-17

18

200

81-29

52

300

254-76

178

400

806-197

609

500

1,904-875

1,029

Adding and subtracting three digit numbers

100

253+315

568

200

750-525

225

300

875+125

1,000

400

981-345

636

500

1,569+451

2,020