Answer :

To determine the value of [tex]\( y \)[/tex] in the equation [tex]\( 5x + 2y = 20 \)[/tex] when [tex]\( x = 0.3 \)[/tex], we will follow these steps:

1. Substitute the given value of [tex]\( x \)[/tex] into the equation:
[tex]\[ 5(0.3) + 2y = 20 \][/tex]

2. Calculate the value of [tex]\( 5 \times 0.3 \)[/tex]:
[tex]\[ 5 \times 0.3 = 1.5 \][/tex]

So the equation becomes:
[tex]\[ 1.5 + 2y = 20 \][/tex]

3. Isolate the term [tex]\( 2y \)[/tex]:
[tex]\[ 2y = 20 - 1.5 \][/tex]

4. Perform the subtraction:
[tex]\[ 20 - 1.5 = 18.5 \][/tex]
So now we have:
[tex]\[ 2y = 18.5 \][/tex]

5. Solve for [tex]\( y \)[/tex] by dividing both sides of the equation by 2:
[tex]\[ y = \frac{18.5}{2} \][/tex]

6. Calculate the division:
[tex]\[ 18.5 \div 2 = 9.25 \][/tex]

Therefore, the value of [tex]\( y \)[/tex] when [tex]\( x = 0.3 \)[/tex] is [tex]\( 9.25 \)[/tex].

The correct answer is [tex]\( \boxed{9.25} \)[/tex].