GCSE Secondary Maths Age 13-17 - Ratio, Proportion & Rates of Change: Percentage - Explained

The video tutorial explains how to calculate percentages without a calculator by first determining 10% of a number and then using that to find other percentages, such as 60%. The example given is calculating 60% of 70 by first finding 10% (which is 7) and then multiplying it by 6 to get 42. The tutorial also discusses the marks allocation for such a question, emphasizing the importance of understanding the process of finding 10% first.

What is the first step in calculating percentages without a calculator?

• Find 50% of the number

• Calculate 10% of the number

• Multiply the number by 2

• Subtract 5 from the number

If 10% of a number is 7, what is 60% of the same number?

• 60

• 70

• 42

• 35

How many times do you multiply the 10% value to find 60%?

• 5 times

• 6 times

• 4 times

• 7 times

What is the total number of marks available for the question discussed?

• One mark

• Two marks

• Three marks

• Four marks

What is the teacher's advice for solving percentage problems?

• Estimate the answer

• Use a calculator

• Always start with 50%

• Begin with 10%