GCSE Secondary Maths Age 13-17 - Number: Odd Numbers - Explained

The video tutorial guides students through the process of identifying the 20th odd number. It begins by listing the first few odd numbers and explains a method to quickly find the 20th odd number without listing all of them. The teacher demonstrates how to group odd numbers into rows and verifies the final answer, which is 39.

What is the task given in Question 3?

• Write down the 15th odd number.

• Write down the 20th even number.

• Write down the 20th odd number.

• Write down the 10th odd number.

Which of the following is the 5th odd number?

• 11

• 9

• 13

• 7

How many odd numbers are there in the first two rows listed by the teacher?

• 20

• 15

• 10

• 5

What is the 20th odd number according to the teacher's calculation?

• 39

• 41

• 37

• 43

Why does the teacher choose not to list all odd numbers up to the 20th?

• To focus on even numbers.

• To avoid making mistakes.

• To save time.

• To make it more challenging.