Multiplication

Array

100

1 row 5 colomus 

5

200

3 rows 10 columns

30

300

5 rows 15 colums

75

400

7 rows 20 columes

140

500

8 rows and 25 colums

200

Repeated Addition

100

5+5+5+5+5=

25

200

10+10+10+10+10+10+10+10+10+10=

100

300

15+15+15+15+15+15+15+15+15+15+15+15+15+15+15=

225

400

20+20+20+20+20+20+20+20+20+20+20+20+20+20+20+20+20+20+20+20=

400

500

25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25+25=

625