Respuesta :

9514 1404 393

Answer:

  4/10 and 10/25

Step-by-step explanation:

If each of the ratios reduces to the same lowest terms, then they are a proportion. All are in lowest terms except the first pair. Reducing those gives ...

  4/10 = 10/25 = 2/5

4/10 and 10/25 form a proportion

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All of the other pairs are pairs of different ratios, so do not form a proportion.