Counting on Addition

27 37 47 57 67

+10 +10 +10 +10

27+40 =

Example:

67

2-digit number with a multiple of ten

Addition

27

20 7

20 40

Example:

67

27 + 40 =

7++

+= 60

=

2-digit number with a multiple of ten

Addition

53

50 3

50 80

Example:

133

53 + 80 =

3++

+= 130

=

2-digit number with a multiple of ten

Addition

97

90 7

90 80

Example:

177

97 + 80 =

7++

+= 170

=

Siti bought the items listed below.

Quantity Items The cost of one unit

Total

4 25

Story booksRulersPencil

sharpeners

$4$2$3

______________________________

Total amount

Practical Application$2 each

$3 each Siti paid the shopkeeper $100.00. How much change will she receive?

=___________

$4 each

• Add $16 + $4 + $15 =

2-digit number with a multiple of ten

$10 $6

$10 $5

$10 + $6 + $4 + $10 + $5

10

+10

20 6 7 8 9 10

+1 +1 +1 +1

= $20 + $10 +

= $35

$5

What is the total cost of two toy cars below?

B$447 $530

$447 = $400 + $40 + $7

$530 = $500 + $30

$447 + $530 = $400 + $500 + $40 + $30 +

= $ 900 + $70 +

$7

= B$977