document.write( "Question 1077694: average age of a boy and a girl is 14 yrs. The average age of the same boy, the girl and her twin sister is 16 yrs. What is the boy's age? \n" ); document.write( "
Algebra.Com's Answer #692164 by amfagge92(93)![]() ![]() You can put this solution on YOUR website! let their ages be a , b and 2b \n" ); document.write( "a+b/2=14....i \n" ); document.write( "a+2b/3=16..ii \n" ); document.write( "solving we have \n" ); document.write( "a+b=28....iii \n" ); document.write( "a+2b=48...iv \n" ); document.write( "a=28-b......v \n" ); document.write( "subtitute a in eqn iv \n" ); document.write( "28-b+2b=48 \n" ); document.write( "b=20 \n" ); document.write( "subtitute b in enq v \n" ); document.write( "a=28-20 \n" ); document.write( "a=8. \n" ); document.write( "the boy's age is 8. \n" ); document.write( " |