document.write( "Question 242785: paddy is three times as old as Siobhana. Seven years ago, he was five times as old as Sibohana.How old is Paddy now? \n" ); document.write( "
Algebra.Com's Answer #177748 by oberobic(2304)\"\" \"About 
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Start by defining your terms.
\n" ); document.write( "p = Paddy's age
\n" ); document.write( "s = Sibohana's age
\n" ); document.write( "Now we set up the givens:
\n" ); document.write( "p = 3s OR Paddy is 3 times Siobhana's age
\n" ); document.write( "p -7 = 5(s-7) OR 7 years ago, Paddy was 5 times Siobhana's age
\n" ); document.write( "Notice that we show BOTH p-7 and s-7 as their ages 7 years ago.
\n" ); document.write( "Substituting the value of p from the first equation into the second:
\n" ); document.write( "3s -7 = 5(s - 7)
\n" ); document.write( "Multiplying through the right side:
\n" ); document.write( "3s -7 = 5s - 35
\n" ); document.write( "Subtracting 3s from both sides:
\n" ); document.write( "-7 = 2s - 35
\n" ); document.write( "Adding 35 to both sides:
\n" ); document.write( "-7 + 35 = 28 = 2s
\n" ); document.write( "Dividing both sides by 2:
\n" ); document.write( "14 = s. Siobhana is 14.
\n" ); document.write( "We know from the setup that:
\n" ); document.write( "p = 3s, so p = 3(14) = 42. Paddy is 42.
\n" ); document.write( "Check your work!
\n" ); document.write( "Substitute the values into the second equation.
\n" ); document.write( "p - 7 = 5(s - 7)
\n" ); document.write( "42 - 7 = 5(14 -7)
\n" ); document.write( "35 = 5(7), which is true.
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