**Elementary School Number Sense Lesson 4: Dividing Fractions**

Today's concept will require a bit of topsy-turvy thinking. It has appeared

**5 times**so far on elementary tests this year, with a median placement at

**question # 34**.

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The main thing to remember with this concept is:

*When dividing by a fraction,*

**multiply by its reciprocal**!**Example 1: 32 ÷ 4/5 = ___**

- This is the same as
**32 x 5/4**. - Divide before you multiply. 32 ÷ 4 =
**8**. - 8 x 5 =
**40**.

**Example 2: 18 ÷ 6/7 = ___**

- This is the same as
**18 x 7/6**. - Divide first: 18 ÷ 6 =
**3**. - 3 x 7 =
**21**.

**Example 3: 4/5 ÷ 2/3 = ___**

- This is the same as
**4/5 x 3/2**. - Multiply straight across: (4 x 3)/(5 x 2) =
**12/10**. - This reduces to
**6/5**.

**Example 4: 3/10 ÷ 15/100 = ___**

- This is the same as
**3/10 x 100/15**. - Multiply straight across: (3 x 100)/(10 x 15); cancel a 0 from the top and bottom to make it (3 x 10)/(1 x 15).
- This becomes
**30/15**, which is**2**.

**Example 5: 9/10 ÷ 9/100 = ___**

- This is the same as
**9/10 x 100/9**. - You can see that the 9's will cancel, as well as a factor of 10.
- The answer is
**10**.

**Example 6: 8/10 ÷ 4/1000 = ___**

- This is the same as
**8/10 x 1000/4**, which reduces to**4/5 x 250**. - Divide first. 250 ÷ 5 =
**50**. - 50 x 4 =
**200**.

**Up Next for Elementary School: ConvTime**