CBSE · Class 6-12

Class 7 · Ganita Prakash

Unit 6 · Class 7Ganita Prakash

Number Play

Divisibility rules and number puzzles.

Lessons

3 concepts

1
Divisibility Rules
Fast tests without full division. By 4: last two digits divisible by 4. By 6: divisible by both 2 and 3. By 8: last three digits divisible by 8.
2
Digit Puzzles
'Which digit at * makes 24*8 divisible by 9?' Sum $2+4+*+8 = 14+*$ . Need $18-14 = 4$ .
3
Number Patterns
Use divisibility to check calculator answers or find missing digits in cryptic sums.

Skills to practise

Skill · medium

Number Play — Practice