Question 50: Find a fraction with a denominator of 7, knowing that when adding the numerator by 16 and multiplying the denominator by 5, the value of that fraction does not change.

Call \(\frac{n}{7}\) (n Z) is the fraction to find

According to the topic we have: \(\frac{n}{7} = \frac{{n + 16}}{{7.5}}\) ⇔ 35. n = 7 (n + 16)

⇔ 35n – 7n = 112 n(35 – 7) = 112 ⇔ n = 112 : 28 n = 4

So the required fraction is \(\frac{4}{7}\)

Retry: \(\frac{4}{7} = \frac{{4 + 16}}{{7.5}} = \frac{{20}}{{35}}\)

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