3. 10 ÷ 2 = 5
How else can we divide 10 by 2?
10 x
1 10 1 10
10 x 2
= 1 x 2
=2= 5
You can multiply by the reciprocal of 2
and you will get the same result.
1
2 and are called multiplicative
2
inverses, or reciprocals.
4. METHOD #1: USING THE RULES
FOR DIVIDING FRACTIONS:
“K. C. F.”
1) Keepthe first fraction.
2) Change the to x.
3) Flip the second fraction.
1 3 1
Ex: a) 5 4 b) 2
4
3 2 6 1
K C FK C Fx= = 1 4
1
2
4
5 x 4 = 20
5. METHOD #2: MODELING
How can the quotient be larger than the
dividend and/or divisor?
1
5 4
This actually means how many ¼-sized
pieces can fit into 5 wholes?
6. MORE MODELING…
3 1
4 2
How many ½-sized pieces fit in ¾?
3
4
1 1
2 2
1 whole and 1 half of the ½-sized pieces fit in the
¾ space, so
= 3 1 1
1
4 2 2
7. EVEN MORE MODELING…
1 3
2
÷ 4
What part of the ¾-sized piece fits in ½?
1
2
3
4
2
of the ¾-sized
3
piece fits in ½
8. METHOD #3: DIVIDING DECIMALS
INSTEAD
Students can turn both fractions into
decimals and can divide those instead:
1 = 0.5 3
= 0.75
2 4
3 1 1 3
÷ = 0.75 ÷ 0.5 ÷ = 0.5 ÷ 0.75
4 2 2 4