If a,b ,and c are positive real numbers such that a(b+c) = 152, b(c+a) =162 , and c(a+b) = 170, then abc is
Choose the correct choice from the following answers
A) a) 672 B) b) 688 C) c) 704 D) d) 720 E) e) 750
ab+bc = 152 --------------------------------------1)   bc+ba = 162---------------------------------------2)   ac+ab = 170---------------------------------------3)   Re-writing equation 3 as follows:   ac+cb = 162 + 8   ac+cb = bc+ba + 8   ac = ba + 8 ............... (4)   Adding (1)(4)   2ac = 160   ac= 80   abc has to be multiple of 80, only 720 fits in   Answer = d) 720
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If a,b ,and c are positive real numbers such that a(b+c) = 152, b(c+a) =162 , and c(a+b) = 170, then abc is