Mathematics Magazine for Grades 1-12  

Grade 1

Theory:

Subtracting Two Digit Numbers without Renaming

How to subtract two-digit numbers (for example 67 - 45).

Place one number above the other so the tens' place digits and ones' place digits are lined up. Draw a line under the bottom number.

67

45

Subtract the bottom ones' place digit (5) from the top ones' place digit (7) and place the difference (2) below the line in the ones' place column.

67

45

  2

Subtract the bottom tens' place digit (4) from the top tens' place digit (6). Place the difference (2) below the line in the tens' place column.

67

45

22

Solutions from the Previous Issue: 

1         It snowed on five days in December. It also snowed on three days in January. How many days did it snow in December and January?

Solution:

5 days + 3 days = 8 days

2         Michael has five candles on a birthday cake. Paul adds eight candles to the cake so that the candles will match Michael's age. How old is Michael?

Solution:

5 candles + 8 candles = 13 candles. Michael is 13 years old.

3         Paul made three apple pies. Amy made one apple pie. How many more pies did Paul make than Amy?

Solution:

3 apple pie – 1 apple pie = 2 apple pie

4         5 lights were on in the house. 2 lights were turned off. How many lights are still on?

Solution:

5 lights - 2 lights = 3 lights are still on.

5         A store has 6 violet candles and 2 orange candles. How many more violet candles does the store have than orange?

Solution:

Proposed Exercises: 

Calculate:

1.        25 – 5 =

2.        63 – 2 =

3.        86 – 3 =

4.        77 + 2 – 8 =