Dive deep into factors, multiples, and the special numbers that build every other number: primes.
A prime number has exactly two factors: 1 and itself. A composite number has more than two factors. The number 1 is neither prime nor composite — it's a special case on its own.
Is 29 a prime number?
Yes, its only factors are 1 and 29
List all prime numbers between 10 and 20.
11, 13, 17, 19
The Highest Common Factor (HCF) of two numbers is the largest number that divides both exactly. The Lowest Common Multiple (LCM) is the smallest number that both numbers divide into exactly.
Find the HCF of 18 and 24.
6
Find the LCM of 4 and 6.
12
1. Is 51 a prime number? (Hint: check if 3 divides it)
2. List all prime numbers less than 10.
3. Find the HCF of 20 and 30.
4. Find the LCM of 5 and 8.
5. Two bells ring every 6 and 8 minutes. If they ring together now, after how many minutes will they ring together again?