Chapter 1

Expanded Form

100

245

2x100+4x10+5x1

200

502

5x100+2x1

300

3546

3x1000+5x100+4x10+6x1

400

35670

3x10000+5x1000+6x100+7x10

500

567091

5x100000+ 6x10000+7x1000+9x10+1x1

Expanded form with index notation

100

520

5x10²+2x10¹

200

456

4x10²+5x10¹+6x1

300

5672

5x10³+6x10²+7x10¹+2x1

400

8705

8x10³+7x10²+5x1

500

567045

5x10⁵+6x10⁴+7x10³+4x10¹+5x1

Partitioning

100

42+12

40+10+2+2=54

200

125+114

100+100+20+10+5+4=239

300

105+133

100+100+30+5+3=238

400

1461+2232

1000+2000+400+200+60+30+1+2 = 3693

500

6345 + 431

6000+300+400+40+30+5+1 = 6776

Compensating

100

25 + 19

25+20-1 = 44

200

44+18

44+20-2 = 62

300

35+98

35+100-2 = 132

400

44-19

44-20+1 = 25

500

236-98

236-100+2 = 138

Doubling/Halving

100

50+52

50+50+2 = 102

200

75+77

75+75+2 = 152

300

65+63

65+65 -2 = 128

400

240-121

240-120-1 = 119

500

482-240

480-240+2 = 242