Respuesta :
a:b = 5:9
b:c = 6:7
Multiply quantity a and b in a:b by 6
(ax6) : (bx6) = (5x6):(9x6) = 30:54
Multiply quantity b and c in b:c by 9
(bx9):(cx9) = (6x9):(7x9) = 54 : 63
So, a:b:c = 30:54:63
And so the ratio a:c = 30:63
Simplify : divide by 3, 10:21.