document.write( "Question 519630: ) The ratio of ages of mother and son is 2:1 Mother was 30 years old when she gave birth to her only daughter who is 5 years younger to her only son. Find the present age of mother. \n" ); document.write( "

Algebra.Com's Answer #345713 by oberobic(2304) $\"\"$ $\"About$

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m = mother's age
\n" ); document.write( "s = son's age
\n" ); document.write( "d = daughter's age
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\n" ); document.write( "Today, ratio of mother's age to son's age is 2:1.
\n" ); document.write( "m = 2s
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\n" ); document.write( "The son is 5 years older than the daughter, so when d was born, s was 5.
\n" ); document.write( "That is d=0 when she is born and s=5
\n" ); document.write( "We're told the mother was 30 then.
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\n" ); document.write( "However, the ratio of mother's to son's ages is unknown at that point in time. It's 2:1 today.
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\n" ); document.write( "Logically, we know that x years later, which is the current day, the ratio is 2:1
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\n" ); document.write( "30+x = 2(5+x)
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\n" ); document.write( "30 + x = 10 + 2x
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\n" ); document.write( "20 = x
\n" ); document.write( "x = 20
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\n" ); document.write( "That means 20 years have gone by.
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\n" ); document.write( "m = 30+20 = 50 years old = mother's present age
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\n" ); document.write( "s = 5+20 = 25 years old, which satisfies the 2:1 ratio.
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\n" ); document.write( "d = 25-5 = 20, if anyone wants to know how old the daughter is.
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\n" ); document.write( "Done. \n" ); document.write( "

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