Hong Kong
Stage 2

# Generalising patterns with fractions in tenths or hundredths

Lesson

You may have already looked at how to write a rule to describe number patterns. Now we are going to extend this and learn how to write general rules using pronumerals

A pronumeral is a letter mathematicians use to represent an unknown value. Watch this value to see how we can use pronumeral to describe patterns with fractions.

#### Worked examples

##### Question 1

Complete the following pattern.

1.  $0.01$0.01 $0.02$0.02 $0.03$0.03 $\editable{}$ $\editable{}$ $\editable{}$ $\editable{}$ $\editable{}$
2. If $c$c belongs to the same pattern, what is the next number?

##### Question 2

Complete the following pattern.

1.  $0.15$0.15 $0.14$0.14 $0.13$0.13 $\editable{}$ $\editable{}$ $\editable{}$ $\editable{}$ $\editable{}$
2. If $x$x belongs to the same pattern, what is the next number?

##### Question 3

Consider the following pattern.

1. What is the pattern?

 $0.03$0.03 $0.11$0.11 $0.19$0.19 $\editable{}$ $\editable{}$ $\editable{}$

The numbers are increasing by $0.08$0.08.

A

The numbers are increasing by $80$80.

B

The numbers are increasing by $8$8.

C

The numbers are increasing by $0.8$0.8.

D
2. Now complete the pattern.

 $0.03$0.03 $0.11$0.11 $0.19$0.19 $\editable{}$ $\editable{}$ $\editable{}$
3. If $x$x belongs to the same pattern, what is the next number?