Primary 5 Percentage
Keywords
- Percent (%)
- Out of 100.
- Whole
- The complete amount, represented by 100%.
- Part
- A portion of the whole.
- Discount
- An amount taken off the original price.
- GST
- Goods and Services Tax added to the price of a taxable purchase.
- Annual interest
- Interest earned or paid in one year.
What percentage means
Percent means “out of 100”. The whole is 100%. A percentage, fraction and decimal can describe the same part.
Choose a shaded part
See worked example
Write 0.3 as a percentage.
- 0.3 = 30 hundredths.
- 30 out of 100 = 30%.
Answer: 30%.
Try together
Write 0.6 as a percentage.
Reveal the answer
0.6 = 60 hundredths = 60%.
Part of a whole and percentage of an amount
To express a part as a percentage, write part over whole and make an equivalent fraction out of 100. To find a percentage of an amount, use that percentage as a fraction out of 100.
Express a part as a percentage
8 out of 20 = ?%
Find a percentage of an amount
20% of 60 = ?
Try together
6 out of 25 counters are blue. What percentage are blue?
Reveal the answer
Multiply the numerator and denominator by 4: 6 out of 25 = 24 out of 100 = 24%.
Discount, GST and annual interest
A discount reduces a price. GST adds tax to a taxable price. Annual interest tells you how much interest is earned or paid in one year.
Choose an example
Try together
A $50 bag has a 10% discount. What is the sale price?
Reveal the answer
Original price = 100%. Sale price = 100% − 10% = 90%. Since 100% → $50, 1% → $0.50. So 90% → $0.50 × 90 = $45.