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- 335
- àï2.2è Reducing Fractions.
- äè Please Reduce the following fractions.
- âSêë6êè2∙3êè 3ê 3
- #êêï1)ï─è =è ─────è =è ───è=è─
- êêë 8êï2∙2∙2êï2∙2ê4
-
- êêë 12êï2∙2∙3êï2∙3êè6
- #êêï2)ï──è =è ─────è =è ───è =è ──
- êêë 38êè2∙19êè19êï19
- éS To Reduce the fraction,ï12/38 , you should first express
- the top and bottom in prime factored form.
- êêêê12êï2∙2∙3
- #êêêê──è =è ─────
- êêêê38êè2∙19
-
- Next, cancel out any like factors that occur on both the top and bottom
- and multiply the remaining factors.
- #êê12êï╖∙2∙3êï2∙3êè6
- #êê──è =è ─────è =è ───è =è ──
- #êê38êè╖∙19êè19êï19
-
- Thus, the fraction,ï12/38 , reduces toï6/19.ïThese two fractions are
- actually equal to each other, and they occupy the same location on the
- number line.ïConsider reducing the fraction,ï12/10.
- #êè12êï╖∙2∙3êï2∙3êï6êè1
- #êè──è =è ─────è =è ───è =è ─èorè1 ─
- #êè10êè╖∙5êè 5êè5êè5
-
- The answer,ï6/5 , can be left in this form or changed to the mixed
- number,ï1 1/5 .ïIt is not more correct to write the answer as a mixed
- number, however some books ask you to write the answer as a mixed
- number.
- 1êêêêê 14
- #êêêïReduce the fraction,ï──.
- êêêêêêè28
-
- êë2êêè1êêè 7
- #ê A)ï─êë B)ï─êë C)ï──êëD)ïå
- êë4êêè2êêè14
- ü
-
- #êêêè14êè╖∙╝êè1
- #êêêè──è =è ─────è =è ─
- #êêêè28êï╖∙2∙╝êï2
- Ç B
- 2êêêêê 24
- #êêêïReduce the fraction,ï──.
- êêêêêêè36
-
- êë2êêè6êêè12
- #ê A)ï─êë B)ï─êë C)ï──êëD)ïå
- êë3êêè9êêè18
- ü
-
- #êêê24êï╖∙╖∙2∙╕êï2
- #êêê──è =è ───────è =è ─
- #êêê36êï╖∙╖∙╕∙3êï3
- Ç A
- 3êêêêêï0
- #êêêïReduce the fraction,ï──.
- êêêêêêè10
-
- êë 1
- #ê A)ï──êëB)ï10êëC)ï0êë D)ïå
- êë10
- ü
-
- êêêêè0
- #êêêêï──è =è 0
- êêêêï10
- Ç C
- 4êêêêê 45
- #êêêïReduce the fraction,ï──.
- êêêêêêè15
-
- êë1êêè 1
- #ê A)ï─êë B)ï──êëC)ï3êë D)ïå
- êë3êêè15
- ü
-
- #êêë 45êï╕∙3∙║êï3
- #êêë ──è =è ─────è =è ─è =è 3
- #êêë 15êè ╕∙║êï1
- Ç C
- 5êêêêê 20
- #êêêïReduce the fraction,ï──.
- êêêêêêè28
-
- êë 5êêï5êêè10
- #ê A)ï──êëB)ï─êë C)ï──êëD)ïå
- êë14êêï7êêè14
- ü
-
- #êêê20êï╖∙╖∙5êï5
- #êêê──è =è ─────è =è ─
- #êêê28êï╖∙╖∙7êï7
- Ç B
- 6êêêêê 18
- #êêêïReduce the fraction,ï──.
- êêêêêêè12
-
- êè3ê1êè9ê3êè 2
- #ë A)ï─ïor 1 ─ë B)ï─ïor 1 ─êC)ï─êèD)ïå
- êè2ê2êè6ê6êè 3
- ü
-
- #êêè 18êï╖∙╕∙3êï3êè1
- #êêè ──è =è ─────è =è ─èorè1 ─
- #êêè 12êï╖∙2∙╕êï2êè2
- Ç A
- 7êêêêê 60
- #êêêïReduce the fraction,ï──.
- êêêêêêè80
-
- êë15êêï2êêè3
- #ê A)ï──êëB)ï─êë C)ï─êë D)ïå
- êë20êêï3êêè4
- ü
-
- #êêë 60êè╖∙╖∙3∙║êè3
- #êêë ──è =è ─────────è =è ─
- #êêë 80êï╖∙╖∙2∙2∙║êï4
- Ç C
- 8êêêêêï48
- #êêêïReduce the fraction,ï───.
- êêêêêêè144
-
- êë1êêè5êêè 3
- #ê A)ï─êë B)ï─êë C)ï──êëD)ïå
- êë3êêè9êêè17
- ü
-
- #êêë48êï╖∙╖∙╖∙╖∙╕êè 1
- #êêè ───è =è ───────────è =è ─
- #êêè 144êï╖∙╖∙╖∙╖∙╕∙3êï3
- Ç A
- 9êêêêê 36
- #êêêïReduce the fraction,ï──.
- êêêêêêè16
-
- êè18ê 2êè 9ê1êë3
- #ë A)ï──ïorï2 ─êB)ï─ orï2 ─ê C)ï─êïD)ïå
- êè 8ê 8êè 4ê4êë4
- ü
-
- #êêï36êï╖∙╖∙3∙3êï9êë1
- #êêï──è =è ───────è =è ─è orè 2 ─
- #êêï16êï╖∙╖∙2∙2êï4êë4
- Ç B
- 10êêêêë19
- #êêêReduce the fraction,ï──.
- êêêêêê 47
-
- êè3êêë5êêë 8
- #ë A)ï─êê B)ï─êê C)ï──êïD)ïå
- êè8êêë7êêë13
- ü
-
- êêêè19
- #êêêè──èis already Reduced.
- êêêè47
- Ç D
- äèPlease find the missing numerator (top number) in order
- êê to construct an equivalent fraction.
- âSë1)ï2ê?êêè2)ï5ê ?
- #êêè─è=è─êêê─è=è──
- êêè3ê6êêê7ê49
-
- êêè2ê4êêê5ê35
- #êêè─è=è─êêê─è=è──
- êêè3ê6êêê7ê49
- éS In order to find the missing numerator in the equation,
- êêêê 5êè?
- #êêêê ─è =è ──
- êêêê 7êï49
-
- it is necessary to divide the "7" into "49".ïThe answer, 7, is then
- multiplied times "5" to get "35".ïThis is the missing numerator.
- êêêê 5êï35
- #êêêê ─è =è ──
- êêêê 7êï49
-
- The fraction,ï5/7 , is actually equal to the fraction,ï35/49.ïIt will
- be necessary in the next section, which is about adding fractions, to
- find missing numerators.
- 11êêêêêêè3ê ?
- #êèFind the missing numerator in the equation,ï─è=è──.
- êêêêêêêë 4ê16
-
- ë3ë12êê3ë10êê3ë15
- # A)ï─ï=ï──êèB)ï─ï=ï──êèC)ï─ï=ï──êD)ïå
- ë4ë16êê4ë16êê4ë16
- ü
-
- êêêê 3êï12
- #êêêê ─è =è ──
- êêêê 4êï16
- Ç A
- 12êêêêêêè5ê?
- #êïFind the missing numerator in the equation,ï──è=è──.
- êêêêêêêë17ê51
-
- ê5ë20êë 5ë15êë 5ë10
- #ïA)ï──ï=ï──ê B)ï──ï=ï──ê C)ï──ï=ï──ëD)ïå
- ë 17ë51êë17ë51êë17ë51
- ü
-
- êêêê 5êï15
- #êêêê──è =è ──
- êêêê17êï51
- Ç B
- 13êêêêêêï3ê ?
- #êïFind the missing numerator in the equation,ï─è=è──.
- êêêêêêêë8ê32
-
- ë3ë 9êê3ë14êê3ë12
- # A)ï─ï=ï──êèB)ï─ï=ï──êèC)ï─ï=ï──êD)ïå
- ë8ë32êê8ë32êê8ë32
- ü
-
- êêêê 3êï12
- #êêêê ─è =è ──
- êêêê 8êï32
- Ç C
- 14êêêêêêè5ê?
- #êïFind the missing numerator in the equation,è─è=è─.
- êêêêêêêë 1ê4
-
- ë 5ë25êë 5ë20êë 5ë15
- # A)è─ï=ï──ê B)è─ï=ï──ê C)è─ï=ï──ëD)ïå
- ë 1ë 4êë 1ë 4êë 1ë 4
- ü
-
- êêêêï5êï20
- #êêêêï─è =è ──
- êêêêï1êè4
- Ç B
- 15êêêêêêï1ê ?
- #êïFind the missing numerator in the equation,ï─è=è──.
- êêêêêêêë4ê60
-
- ë1ë15êê1ë12êê1ë20
- # A)ï─ï=ï──êèB)ï─ï=ï──êèC)ï─ï=ï──êD)ïå
- ë4ë60êê4ë60êê4ë60
- ü
-
- êêêêï1êï15
- #êêêêï─è =è ──
- êêêêï4êï60
- Ç A
- 16êêêêêêï11ê?
- #êïFind the missing numerator in the equation,ï──è=è──.
- êêêêêêêë16ê64
-
- ë11ë22êë11ë33êë11ë44
- # A)ï──ï=ï──ê B)ï──ï=ï──ê C)ï──ï=ï──ëD)ïå
- ë16ë64êë16ë64êë16ë64
- ü
-
- êêêê 11êï44
- #êêêê ──è =è ──
- êêêê 16êï64
- Ç C
- äïPlease find the Least Common Multiple of the following
- êênumbers.
- âS
- êêThe Least Common Multiple of 8 and 14 is 56.
-
- êêThe Least Common Multiple of 3 and 4 is 12.
- éS To find the Least Common Multiple of 8 and 14, you should
- express each number in prime factored form.
- êêêêè8è =è 2∙2∙2
- êêêêï14è =è 2∙7
-
- Now construct a third number that has all the factors that occur in the
- factorizations of 8 and 14.
- #êêï8 ──── 2∙2∙2 ───┐
- #êêêêè ┼─── 2∙2∙2∙7 ──── 56
- #êê 14 ──── 2∙7──────┘
-
- Notice that there must be three factors of "2" in the Least Common
- Multiple.ïEvery factor of 8 and 14 has to be present, in the Least
- Common Multiple, the largest number of times it occurs in any individual
- factorization.ïThe Least Common Multiple is the number 56.ïIt is the
- smallest number that both 8 and 14 divide into evenly.ïWe will need to
- find Least Common Multiples (denominators) in the next section on
- adding fractions.
- 17
- êê Find the Least Common Multiple of 7 and 21.
-
-
- êA)ï42êëB)ï21êëC)ï35êëD)ïå
- ü
-
- #êêè 7 ───────────────┐
- #êêêêê┼───── 3∙7 ───── 21
- #êêè21 ───── 3∙7 ─────┘
- Ç B
- 18
- êê Find the Least Common Multiple of 14 and 42.
-
-
- êA)ï42êëB)ï84êëC)ï56êëD)ïå
- ü
-
- #êêï14 ───── 2∙7──────┐
- #êêêêë ┼───── 2∙3∙7──── 42
- #êêï42 ─── 2∙3∙7 ─────┘
- Ç A
- 19
- êêFind the Least Common Multiple of 44 and 12.
-
-
- êA)ï144êè B)ï660êè C)ï132êè D)ïå
- ü
-
- #êêï44 ─── 2∙2∙11 ────┐
- #êêêêë ┼─── 2∙2∙3∙11 ── 132
- #êêï12 ─── 2∙2∙3 ─────┘
- Ç C
- 20
- êêFind the Least Common Multiple of 3, 9, and 21.
-
-
- êA)ï72êëB)ï63êëC)ï36êëD)ïå
- ü
-
- #êêè 3 ────────────────┐
- #êêêêê │
- #êêè 9 ──── 3∙3 ───────┼─── 3∙3∙7 ───── 63
- #êêêêê │
- #êêè 21 ─── 3∙7 ───────┘
- Ç B
-
-
-