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Number Theory

Level 28 - realistic untimed

Rule for 12

6 visual blocks - structure tests

1

Read the shape

Level 28 visual plan for Rule for 12
Look for digit and factor structure. Rule for 12.

Look for digit and factor structure. Rule for 12.

2

Pick the method

Number Theory: block 2 Visual guide level shape Rule for 12Pick the methodUse divisibility, remainders, GCD, or LCM. image-first, then practice
Use divisibility, remainders, GCD, or LCM.

Use divisibility, remainders, GCD, or LCM.

3

First move

Number Theory: block 3 Visual guide level shape Rule for 12First moveRun the cheapest test first. image-first, then practice
Run the cheapest test first.

Run the cheapest test first.

4

Check

Number Theory: block 4 Visual guide level shape Rule for 12CheckUse GCD x LCM = product when relevant. image-first, then practice
Use GCD x LCM = product when relevant.

Use GCD x LCM = product when relevant.

5

Play the mode

Number Theory: block 5 Visual guide level shape Rule for 12Play the modeSpend the extra second on the check. image-first, then practice
Spend the extra second on the check.

Spend the extra second on the check.

6

Watch-out

Number Theory: block 6 Visual guide level shape Rule for 12Watch-outDo not trial-divide every number. image-first, then practice
Do not trial-divide every number.

Do not trial-divide every number.

Level 27 Level 29

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