document.write( "Question 1164747: Robert is thinking that his father is 7 years older than twice his age, his grandfather is 4 years less than twice his father’s age. If Robert’s grandfather is 70 years old, how old is Robert ? \n" ); document.write( "

Algebra.Com's Answer #789173 by MathTherapy(10555) $\"\"$ $\"About$

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\n" ); document.write( "Robert is thinking that his father is 7 years older than twice his age, his grandfather is 4 years less than twice his father’s age. If Robert’s grandfather is 70 years old, how old is Robert?
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Let Richard's age be R
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document.write( "Then his father's is: 2R + 7, and his grandfather's is: 2(2R + 7) - 4
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document.write( "We then get: 2(2R + 7) - 4 = 70
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document.write( "4R + 14 - 4 = 70
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document.write( "4R = 60
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document.write( "Richard or  \n" );
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