Question

If a, b and c are positive, and if ab= 2, bc = 3 and ac = 6, what is a + b + c?

Answer 1

trial and error i have my answer which is 6, but i dont know the solution

Answer 2

just substitute...

Answer 3

b=2/a, c=6/a so from bc = 3,
2/a * 6/a = 3. so a=2.
b=1, c=3...
a+b+c = 6

Answer 4

ab*bc*ac=6*6
abc = 6
a+b+c =x
a(abc) +abc*b + abc*c = 6x
6*2 + 3*2 + 6*3 = 6x
x = 2 + 1 + 3 = 6

Answer 5

ohhh!!!

Answer 6

@Ishaan94 , that's nice!!!

Answer 7

Thanks :-)

Answer 8

nice solutions .. thanks!

Answer 9

hey @Ishaan94 and @dpalnc
ab*bc*ca=6*6
abc=6
using AM>=GM
(a+b+c)/3>=(abc)^(1/3)
a+b+c>=3(6)^(1/3)=5.45... is it correct...??