Question 42: Find x knowing \(\begin{array}{l} \frac{x}{7} = \frac{6}{{21}}\end{array}\)
By property of two equal fractions, we have:
\(\begin{array}{l} \frac{x}{7} = \frac{6}{{21}}\\ 21.x = 7.6\\ 21.x = 42\\ x = 42:21 \\ x = 2 \end{array}\)
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