Mystery 1
Mystery 2
400

1a 

Dot form and "unit way"

0.5

400

1b 

Dot form and "unit way"

0.04

500

2a

9 ones divided by 3  +   36 hundredths divided by 3

3 ones + 12 hundredths

3 + 0.12

3.12

500

1c

Dot form and "unit way"

0.009

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