Question 48: Find x, y, z know: \({x \over 3} = {y \over 8} = {z \over 5}\) and \(x + y – z = 30\)

\( {x \over 3} = {y \over 8} = {z \over 5}\) and x + y – z = 30

According to the property of the sequence of equal ratios, we have: \({x \over 3} = {y \over 8} = {z \over 5} = {{x – z + y} \over {3 – 5 + 8}} = {{30} \over 6} = 5\)

\({x \over 3} = 5 \Rightarrow x = 3.5 = 15;{y \over 8} = 5 \Rightarrow y = 8.5 = 40;{z \over 5} = 5 \Rightarrow z = 5.5 = 25\ )