the ratio of tomatoes to red apples is
![(2)/(5)](https://img.qammunity.org/2023/formulas/mathematics/high-school/om8wnjmclbbj2aib1jnmxrv7s0auq966q0.png)
this ratio must be the same when you have 20 tomatoes, this means that:
![(2)/(5)=(20)/(x)](https://img.qammunity.org/2023/formulas/mathematics/college/7knnjpttkgn90srnnymgl7qpodbt8px98s.png)
where x is the (unknow) number of apples. Hence, we have:
![\begin{gathered} (2)/(5)=(20)/(x)\Rightarrow x((2)/(5))=20 \\ \text{hence} \\ x=(20)/((2)/(5)) \\ \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/udy1fkjp2mfgu518k2mse3i7m0rmnt429g.png)
then, we need to divide 20 into 2/5. We can do that by applying the "sandwich law":
![\begin{gathered} x=(20)/((2)/(5))=((20)/(1))/((2)/(5)) \\ x=(20\cdot5)/(1\cdot2) \\ x=10\cdot5 \\ x=50 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/3sseem16ndfhfie5cqxg0ktww7j1rvv9uh.png)
therefore, if there are 20 tomatoes, we have 50 apples.