1. We are learning to find percentages
of 3 digit numbers.

2. What does % mean?
per
cent
for every
100

3. To find 1% of a number ÷ by 100
Find 1% of 225
225 ÷ 100
(move all digits 2
places to the right)
225.
1% of 225 =
.2 25

4. To find 10% of a number ÷ by 10
Find 10% of 376
376 ÷ 10
(move all digits 1
place to the right)
376.
10% of 376 =
.37 6

5. Can we use this information
To find 11% of a number?
10% + 1% = 11%

6. Find 11% of 352
352 ÷ 100 =
352.
3.52
352 ÷ 10 =3.52
352.
3 .5 2
35.2
3.52
35.2
+
27.83

7. Find 2% of 453
1% of 453
453 ÷ 100 =4.53
1% x 2 = 2%
4.53
x 2
60
1
9
2 x 3 = 6
2 x 5 = 10
(carry the 1)
2 x 4 = 8 + 1 = 9
The decimal point goes
between the 9 and the 0.
There are 2 digits after the
decimal point in the sum
so we need 2 digits after
the decimal point in the answer .
2% of 453 =

8. Use these methods to find
12% of 563
Hint: add together
10%, 1% and 1%
56.3 + 5.63 + 5.63 =
16% of 285
Hint: add together
10%, 6 x 1%
28.5 + (6 x 2.85) =

9. Can you find
20% of 621?
Hint: 20% =
10% + 10%
or 10% x 2
621 ÷ 10 = 62.1
62.1
62.1+
62.1
x 2
124.2 124.2
20% of 621 = 124.2

10. Can you find
20% of 621?
Hint: 20% =
10% + 10%
or 10% x 2
621 ÷ 10 = 62.1
62.1
62.1+
62.1
x 2
124.2 124.2
20% of 621 = 124.2