Answer :

To find the numerical length of the expression [tex]\(6x + 31\)[/tex] that matches one of the given choices, we need to determine the value of [tex]\(x\)[/tex] that would satisfy the condition [tex]\(6x + 31 = \text{one of the choices}\)[/tex].

Let's solve this step-by-step for each choice:

1. Choice a: 151
[tex]\[ 6x + 31 = 151 \][/tex]
Subtract 31 from both sides:
[tex]\[ 6x = 151 - 31 \][/tex]
[tex]\[ 6x = 120 \][/tex]
Divide by 6:
[tex]\[ x = \frac{120}{6} = 20 \][/tex]
Therefore, for [tex]\( x = 20 \)[/tex], [tex]\( 6x + 31 = 151 \)[/tex].

2. Choice b: 115
[tex]\[ 6x + 31 = 115 \][/tex]
Subtract 31 from both sides:
[tex]\[ 6x = 115 - 31 \][/tex]
[tex]\[ 6x = 84 \][/tex]
Divide by 6:
[tex]\[ x = \frac{84}{6} = 14 \][/tex]
Therefore, for [tex]\( x = 14 \)[/tex], [tex]\( 6x + 31 = 115 \)[/tex].

3. Choice c: 33
[tex]\[ 6x + 31 = 33 \][/tex]
Subtract 31 from both sides:
[tex]\[ 6x = 33 - 31 \][/tex]
[tex]\[ 6x = 2 \][/tex]
Divide by 6:
[tex]\[ x = \frac{2}{6} \approx 0.333 \][/tex]
Therefore, for [tex]\( x \approx 0.333 \)[/tex], [tex]\( 6x + 31 \approx 33 \)[/tex].

4. Choice d: 14
[tex]\[ 6x + 31 = 14 \][/tex]
Subtract 31 from both sides:
[tex]\[ 6x = 14 - 31 \][/tex]
[tex]\[ 6x = -17 \][/tex]
Divide by 6:
[tex]\[ x = \frac{-17}{6} \approx -2.833 \][/tex]
Therefore, for [tex]\( x \approx -2.833 \)[/tex], [tex]\( 6x + 31 \approx 14 \)[/tex].

After checking all choices, we see that the correct solution [tex]\( x = 20 \)[/tex] corresponds to choice (a) [tex]\( 151 \)[/tex]. Thus, the correct numerical length of [tex]\( 6x + 31 \)[/tex] is:

[tex]\[ \boxed{151} \][/tex]