Answer :

Sure, let's solve this step-by-step!

1. Let's denote the number Janet picked as [tex]\( x \)[/tex].

2. According to the problem, Janet first added 7 to the number:
[tex]\[ x + 7 \][/tex]

3. Then, she multiplied the result by 2:
[tex]\[ 2 \times (x + 7) \][/tex]

4. Next, she subtracted 4 from the outcome:
[tex]\[ 2(x + 7) - 4 \][/tex]

5. We are given that the final result is 28:
[tex]\[ 2(x + 7) - 4 = 28 \][/tex]

6. To find [tex]\( x \)[/tex], let's solve this equation step-by-step. First, simplify the expression on the left:
[tex]\[ 2(x + 7) - 4 = 28 \][/tex]
Expand the terms inside the parenthesis:
[tex]\[ 2x + 14 - 4 = 28 \][/tex]
Combine like terms:
[tex]\[ 2x + 10 = 28 \][/tex]

7. Solve for [tex]\( x \)[/tex] by isolating it on one side of the equation. First, subtract 10 from both sides:
[tex]\[ 2x = 28 - 10 \][/tex]
[tex]\[ 2x = 18 \][/tex]

8. Finally, divide both sides by 2:
[tex]\[ x = \frac{18}{2} \][/tex]
[tex]\[ x = 9 \][/tex]

So, Janet originally picked the number [tex]\( 9 \)[/tex].