Question 828250
1)1/a+1/b    =1/6,
2)    1/b+1/c=1/10,
add 
1/a+2/b+1/c=1/6+1/10
3)1/a    +1/c=1/15,
subtract
2/b=1/6+1/10-1/15
b=10

1/a+1/10=1/6
1/a+3/30=5/30
1/a=2/30=1/15
a=15
1/c=0
c=undefined




1/a+1/b+1/c=1/x