Answer :

To find the unknown [tex]\( x \)[/tex] in the proportion [tex]\(\frac{7}{10} = \frac{x}{2}\)[/tex], follow these steps:

1. Set up the proportion:
[tex]\[ \frac{7}{10} = \frac{x}{2} \][/tex]

2. Cross-multiply to eliminate the fractions:
[tex]\[ 7 \times 2 = 10 \times x \][/tex]

3. Perform the multiplication on both sides of the equation:
[tex]\[ 14 = 10x \][/tex]

4. Isolate [tex]\( x \)[/tex] by dividing both sides of the equation by 10:
[tex]\[ x = \frac{14}{10} \][/tex]

5. Simplify the fraction if possible:
[tex]\[ x = 1.4 \][/tex]

The unknown [tex]\( x \)[/tex] in the proportion [tex]\(\frac{7}{10} = \frac{x}{2}\)[/tex] is therefore [tex]\( 1.4 \)[/tex]. Given the provided answer choices, none of the options exactly match, which suggests that there might be an error in the selections given.