Page 171 - New Medley 4 Semester 2 PDF (Merged)

B. Observe and extend the patterns.

1. … 2. …

3. … 4. …

Number Patterns

Patterns give us ideas to solve the problems without doing actual calculations.

Patterns in Addition and Subtraction

Observe the patterns and fill in the blanks.

1. 1 + 2 + 3 = 6 2.

2 + 3 + 4 = 9 280

3 + 4 + 5 = 12 80 120 160

4 + 5 + 6 = 15 30 50 70 90

5 + 6 + 7 = 18 10 20 30 40 50

6 + 7 + 8 = 21
In the above pattern, the
7 + 8 + 9 = block has the number equal

to the sum of two numbers
8 + 9 + 10 =
below it.
In the above pattern,
the sum increases by 3.

3. 10 – 1 = 9 4. 95 60 45 20

100 – 1 = 99 35 15 25

1000 – 1 = 999 10

10000 – 1 = 9999

100000 – 1 = 99999

1000000 – 1 =

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