35 Adding Fractions Add 1 1 2 Estimate the sum x = 5 5 8 8 40 32 40 67 = 12740 Find the least common...
13
35 Adding Fractions Add 1 1 2 Estimate the sum x = x = x = x = 5 5 8 8 40 32 40 67 = 1 1 27 27 40 40 Find the least common denominato ~ ...(find the LCM of 8 and 5 ~ 8: 8, 16, 24, 32, 40 ~ 5: 5, 10, 15, 20, 25, 30, 35, ~ The LCM is 40. Change both denominators to 4 ...then change both numerator Add the new numerators, then keep the denominator the same. Convert to a mixed number mixed number. Is the sum close to the estimate? 40
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Transcript of 35 Adding Fractions Add 1 1 2 Estimate the sum x = 5 5 8 8 40 32 40 67 = 12740 Find the least common...
35
Adding FractionsAdd1
1
2
Estimate the sum
x =
x = x =
x = 55
88
40
32
40
67 = 11272740 40
Find the least common denominator~ ...(find the LCM of 8 and 5)..
~ 8: 8, 16, 24, 32, 40~ 5: 5, 10, 15, 20, 25, 30, 35, 40
~ The LCM is 40.
Change both denominators to 40...then change both numerators
Add the new numerators, then keep the denominator the same.Convert to a mixed numbermixed number.
Is the sum close to the estimate?
40
Adding Fractions
18
Adding Mixed NumbersAdd
2
4
6
Estimate the sum
x =
x = x =
x = 22
55
20
5
20
23 = 11 3 3 2020
Find the least common denominator~ ...(find the LCM of 10 and 4)..
~ 10: 10, 20, 30, 40~ 4: 4, 8, 12, 16, 20 ...
~ The LCM is 20.
Change both denominators to 20...then change both numerators
Add the new numerators, then keep the denominator the same.Convert to a mixed numbermixed number.
Is the sum close to the estimate?
20
910
1
144
Add the whole numbers to the sum.
+55
66 3 3 2020
39
Subtracting FractionsSubtract1
1
0
Estimate the difference
x =
x = x =
x = 33
77
42
35
42
4 2 2 2121
Find the least common denominator~ ...(find the LCM of 14 and 6)
~ 14: 14, 28, 42, 56, 70, 84...~ 6: 6, 12, 18, 24, 30, 36, 42...
~ The LCM is 42.
Change both denominators to 42...then change both numerators
Subtract the new numerators, then keep the denominator the same.
Simplify by finding the GCF ~ 4: 1, 2, 4 ~ 42: 1, 2, ...
Is the sum close to the estimate?
42
1314–
56
–
÷ = ÷ = 2
2
–
Subtracting Fractions
Rewrite each mixed number by borrowing.
4 9
4
Take one from 4 (now you have 3...)...then add it back to the
fraction\3
99
+
=
1393
Remember: 1 = 99
Subtracting Mixed Numbers
711
2
18111
=23
1
53
=59
8
1497
=38
10
1189
=
16
Subtracting Mixed Numbers
8
7
1
Estimate the difference
x =
x = x =
x = 88
33
24
21
24
19 19 2424
Find the least common denominator~ ...(find the LCM of 3 and 8)..
~ 3: 3, 6, 9, 12, 15, 18, 21, 24~ 8: 8, 16, 24
~ The LCM is 24.
Change both denominators to 24...then change both numerators
Subtract the new numerators, then keep the denominator the same.
237
786
–
To avoid negative fraction, let’s borrow from the whole number
Take one from 7 (now you have 6...)...then add it back to the fraction
\6
2424
+ =4024
–
Is the estimate close to the difference?
Adding Mixed Numbers
Subtracting Mixed Numbers
4 9
4 • 9
Estimate the product. 4 • 9 = 36
Convert each to a simple fraction
40 9
•
9 1
=\ \
11
11 40 1 =40
Cross-simplify.
Multiply numerators, then denominators
Simplify the product.
Multiplying Fraction and Mixed NumbersMultiplying Fraction and Mixed Numbers
40 9
9 1
•
Multiplying Fraction and Mixed NumbersMultiplying Fraction and Mixed Numbers
Dividing Fractions and Mixed NumbersDividing Fractions and Mixed Numbers
1. 47
47
74
2. 10
101118
1 10
8 11
3. 381
Original number
Fraction Reciprocal
4. 12
= 2
5. 6 16
=
6. 1 = 1
7.251 5
7=
3 8 5 ÷ 9
Estimate the quotient. 5 ÷ 9 12 Convert each to a simple fraction
5 1 ÷ 75
8
=\ \
11
1717
8 17
Cross-simplify.
Multiply numerators, then denominators
Dividing Fractions and Mixed NumbersDividing Fractions and Mixed Numbers
51 • 8
75
Keepthe first
fraction the same
Changethe division
to multiplicatio
n
Flipthe 2nd fraction
Dividing Fractions and Mixed NumbersDividing Fractions and Mixed Numbers
