Answer:
Roderick has created the correct orange color.
Explanation:
The orange color required mixing 5 parts of red paint with 7 parts of yellow paint. The ratio is given below:
[tex]\operatorname{Re}d\colon\text{Yellow}=5\colon7[/tex]Roderick mixed 15 parts of red paint with 21 parts of yellow paint. This is expressed in ratio as:
[tex]\begin{gathered} \operatorname{Re}d\colon\text{Yellow}=15\colon21 \\ \text{Divide both sides by 3} \\ \frac{15}{3}\colon\frac{21}{3}=5\colon7 \end{gathered}[/tex]Since the two ratios reduces to the same value, they are equivalent, thus Roderick has created the correct orange color.