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Задача Задача №2631618
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Аноним
15 января 2025 11:14 · публичный вопрос
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Аноним

2 5/9:х=1 2/21: 2 1/7

Ответ нейросети
15 января 2025 11:14

To solve the proportion \( \frac{2 \frac{5}{9}}{x} = \frac{1 \frac{2}{21}}{2 \frac{1}{7}} \), we first convert the mixed numbers into improper fractions.

  1. Convert \( 2 \frac{5}{9} \) into an improper fraction:

\[ 2 \frac{5}{9} = \frac{2 \times 9 + 5}{9} = \frac{18 + 5}{9} = \frac{23}{9} \]

  1. Convert \( 1 \frac{2}{21} \) into an improper fraction:

\[ 1 \frac{2}{21} = \frac{1 \times 21 + 2}{21} = \frac{21 + 2}{21} = \frac{23}{21} \]

  1. Convert \( 2 \frac{1}{7} \) into an improper fraction:

\[ 2 \frac{1}{7} = \frac{2 \times 7 + 1}{7} = \frac{14 + 1}{7} = \frac{15}{7} \]

Now, we rewrite the original equation with the improper fractions:

\[ \frac{\frac{23}{9}}{x} = \frac{\frac{23}{21}}{\frac{15}{7}} \]

Next, simplify the right side:

\[ \frac{\frac{23}{21}}{\frac{15}{7}} = \frac{23}{21} \times \frac{7}{15} = \frac{23 \times 7}{21 \times 15} = \frac{161}{315} \]

Now we can set up the equation:

\[ \frac{\frac{23}{9}}{x} = \frac{161}{315} \]

To solve for \( x \), we cross-multiply:

\[ 23 \times 315 = 161 \times 9x \]

Calculating \( 23 \times 315 \):

\[ 23 \times 315 = 7245 \]

Now, the equation is:

\[ 7245 = 161 \times 9x \]

Next, calculate \( 161 \times 9 \):

\[ 161 \times 9 = 1449 \]

Now we have:

\[ 7245 = 1449x \]

To solve for \( x \):

\[ x = \frac{7245}{1449} \]

Calculating \( \frac{7245}{1449} \):

\[ x = 5 \]

Thus, the value of \( x \) is:

\[ \boxed{5} \]