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chapter4.1b
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àï4.1è Introduction to Ratios.
äè Please write the following ratios in simplest form.
âïWrite the ratio of 20 ft. to 24 ft. using three different
notations.
è Fraction Notationê Colon Notationê "is to" Notation
è 20 ft.è20è5êè20 ft. : 24 ft.ê20 ft. is to 24 ft.
#è ────── = ── = ─êê20 : 24êê 20 is to 24
è 24 ft.è24è6êê 5 : 6êêè5 is to 6
éS A ratio is a comparison of two numbers that have the same
units.ïThe two quantities "20 ft." and "24 ft." have the same units
since they are both in "feet".ïThese two quantities can be compared
three differentïways.ïProbably the most frequent method of comparison
is as a fraction.
êêêè20 ft.ë20ë5
#êêêè──────ï=ï──ï=ï─
êêêè24 ft.ë24ë6
êêêêêêêêï20
#Note that the units, "ft.", cancel out and the fraction,ï── , is
êêêêêêêêï24
reduced to simplest form.
ëThe second method of comparison is done by using a colon, ":".
êêè20 ft. : 24 ft.ï=è20 : 24è=è5 : 6
è The third method of comparison is by using the expression, "is to".
êè20 ft. is to 24 ft.è=è20 is to 24è=è5 is to 6
èThese methods of comparison of two numbers having the same units
are the three ways you can express a ratio.
ï1
êê Write the ratio of 5 to 7 using the Fraction Notation.
êë7êê5
#ê A)ï─êèB)ï─êèC)ï5 : 7ê D)ïå
êë5êê7
ü
êêêêê5
#êêêêê─
êêêêê7
ÇïB
ï2
êê Write the ratio of 25 to 40 in simplest form using the
êê Fraction Notation.
êë8êêêê 5
#ê A)ï─êèB)ï8 : 5ë C)ï─êëD)ïå
êë5êêêê 8
ü
êêêêè25ë 5
#êêêêè──ï=è─
êêêêè40ë 8
ÇïC
ï3
êê Write the ratio of 50 cm to 40 cm in simplest form using
êê Fraction Notation.
êë5
#ê A)ï─êèB)ï50 is to 40èC)ï5 : 4êïD)ïå
êë4
ü
êêêë50 cmë50ë 5
#êêêë─────ï=ï──ï=è─
êêêë40 cmë40ë 4
ÇïA
ï4
êëWrite the ratio of 20 ft. to 28 ft. in simplest form using
êëFraction Notation.
êêêêêêë5
#ê A)ï7 : 5ë B)ï20 is to 28ëC)ï─êèD)ïå
êêêêêêë7
ü
êêêë20 ft.è 20ë 5
#êêêë─────ï=ï──ï=è─
êêêë28 ft.è 28ë 7
ÇïC
ï5
êëWrite the ratio of 8 in. to 2 ft. in simplest form using the
êëFraction Notation.
êë1êê4
#ê A)ï─êèB)ï─êê C)ï8 : 2ë D)ïå
êë3êê1
üê Since ratios must have the same units, it is necessary
to change 2 ft. to 24 inches before reducing.
êêï8 in.ë8 in.ë 8ë1
#êêï─────ï=ï─────ï=ï──ï=ï─
êêï2 ft.ë24 in.è 24ë3
ÇïA
ï6
ïWrite the ratio of 4 dimes to 16 nickels in simplest form using the
ïFraction Notation.
êë1êê1êêë1
#ê A)ï─êèB)ï─êê C)ï─êèD)ïå
êë2êê4êêë8
üê Since ratios must have the same units, it is necessary
to change 4 dimes to 8 nickels before reducing.
êè4 dimesê 8 nickelsë 8ë1
#êï──────────ï=ï──────────ï=ï──ï=ï─
êï16 nickelsë16 nickelsë16ë2
ÇïA
ï7
êê Write the ratio of 5 to 4 in simplest form using the
êê Colon Notation.
ê A)ï5 : 4ë B)ï4 : 5ê C)ï5 is to 4ëD)ïå
ü
êêêêè 5 : 4
ÇïA
ï8
êê Write the ratio of 20 to 16 in simplest form using the
êê Colon Notation.
êêêêêêï10
#ê A)ï10 : 8ëB)ï5 : 4ê C)ï──êèD)ïå
êêêêêêè8
ü
êêêë20 : 16ï=è5 : 4
ÇïB
ï9
êWrite the ratio of 14 lbs. to 35 lbs. in simplest form using the
êColon Notation.
ê A)ï35 : 14è B)ï2 : 5ê C)ï14 is to 35èD)ïå
ü
êè 14 lbs. : 35 lbs.ï=ï14 : 35ï=ï2 : 5
ÇïB
ï10
êWrite the ratio of 14 oz. to 21 oz. in simplest form using the
êColon Notation.
êë14êë 2
#ê A)ï──êïB)ï─êëC)ï2 : 3êïD)ïå
êë21êë 3
ü
êêè 14 oz. : 21 oz.ï=ï14 : 21ï=ï2 : 3
ÇïC
ï11
êWrite the ratio of 8 oz. to 2 lbs. in simplest form using the
êColon Notation.
ê A)ï1 : 4ë B)ï4 : 1ê C)ï8 is to 32è D)ïå
ü
êêSince ratios must have the same units, it is necessary
to change 2 lbs. to 32 oz.
è 8 oz. : 2 lbs.ï=è8 oz. : 32 oz.ï=ï8 : 32ï=ï1 : 4
ÇïA
ï12
êWrite the ratio of 8 ft. to 4 yds. in simplest form using the
êColon Notation.
ê A)ï8 : 4ë B)ï2 : 3ê C)ï2 : 1êïD)ïå
ü
êêSince ratios must have the same units, it is necessary
to change 4 yds. to 12 ft.
è 8 ft. : 4 yds.ï=è8 ft. : 12 ft.ï=ï8 : 12ï=ï2 : 3
ÇïB
ï13
êêïWrite the ratio of 5 to 7 in simplest form using the
êêï"is to " Notation.
êêêêêêë 5
#ëA)ï5 is to 7ëB)ï7 is to 5ê C)ï─ê D)ïå
êêêêêêë 7
ü
êêêêè5 is to 7
ÇïA
ï14
êêWrite the ratio of 26 to 14 in simplest form using the
êê"is to " Notation.
êêêêè 7
#êA)ï7 is to 13ë B)ï──êC)ï13 is to 7è D)ïå
êêêêè13
ü
êêêï26 is to 14ï=ï13 is to 7
ÇïC
ï15
êïWrite the ratio of 12 mi. to 16 mi. in simplest form using the
êï"is to " Notation.
êè 4
#êA)ï─êïB)ï3 is to 4êC)ï3 : 4êD)ïå
êè 3
ü
êë12 mi. is to 16 mi.ï=è12 is to 16ï=ï3 is to 4
ÇïB
ï16
êïWrite the ratio of $36 to $24 in simplest form using the
êï"is to " Notation.
êêêêï3
#êèA)ï3 : 2êB)ï─êïC)ï3 is to 2èD)ïå
êêêêï2
ü
êê $36 is to $24ï=ï36 is to 24ï=ï3 is to 2
ÇïC
ï17
ëWrite the ratio of 24 hours to 4 days in simplest form using the
ë"is to" Notation.
è A)ï1 is to 4ëB)ï6 is to 1ëC)ï4 is to 9ëD)ïå
ü
êïSince ratios must have the same units, it is necessary to
change 24 hours to 1 day.
ê24 hours is to 4 daysï=ï1 day is to 4 daysï=ï1 is to 4
ÇïA
ï18
ëWrite the ratio of 3 quarts to 2 gal. in simplest form using the
ë"is to" Notation.
êêêêêêï3
#è A)ï3 is to 8ëB)ï3 : 8êïC)ï─êèD)ïå
êêêêêêï8
ü
êïSince ratios must have the same units, it is necessary to
change 2 gal. to 8 quarts.
ë3 quarts is to 2 gal.ï=ï3 quarts is to 8 quartsï=ï3 is to 8
ÇïA