document.write( "Question 969428: Please help me with a simple solution. Help for Primary 5 maths.
\n" ); document.write( "14 years ago, when Mina celebrated her birthday with her family, the ratio of the age of Mina to Mina's sister was 7:9. This year, the ratio of the age of Mina to Mina's sister is 7:8. How old is Mina now? \n" ); document.write( "
Algebra.Com's Answer #592327 by Boreal(15235)\"\" \"About 
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The ratio of their ages now is 7x/8x, so we need to find x\r
\n" ); document.write( "\n" ); document.write( "14 years ago ( 7x-14)/(8x-14) the ratio was 7/9\r
\n" ); document.write( "\n" ); document.write( "This is a proportion problem solved with cross multiplication.\r
\n" ); document.write( "\n" ); document.write( "(7x-14) *9=(8x-14) *7\r
\n" ); document.write( "\n" ); document.write( "Distribute
\n" ); document.write( "63x-126=56x -98
\n" ); document.write( "solve by first moving the x over, subtracting 56x from both sides
\n" ); document.write( "7x-126=-98
\n" ); document.write( "add 126 to both sides
\n" ); document.write( "7x=28\r
\n" ); document.write( "\n" ); document.write( "x=4
\n" ); document.write( "The ratio is 7x/8x, so Mina is 28. That is the answer asked for.\r
\n" ); document.write( "\n" ); document.write( "Her sister is now 32\r
\n" ); document.write( "\n" ); document.write( "14 years ago, Mina was 14 and her sister 18. That is a 7:9 ratio.
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