document.write( "Question 1338: John is 4 years old & his sister is three times as old as he. When John is 12,
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Algebra.Com's Answer #408 by usyim88hk(158) $\"\"$ $\"About$

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So when John is 4 years old his sister is three times as old as he, which means that she is 4*3 = 12 years old at that time, so as John become 12, meaning that 8 years passed, so add 8 to his sister's age, 12+8 = 20, so his sister is 20 years old when John is 12 years old. \n" ); document.write( "

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