To determine how many hours Christiana needs to work, we first calculate how much money she must earn from her hourly wage after accounting for the tip she will receive.
- Total amount needed: $130 (for car insurance)
- Tip received: $18
First, we subtract the tip from the total amount needed:
\[ 130 - 18 = 112 \]
Now, we need to calculate how many hours she must work to earn the remaining $112 at her hourly wage of $14 per hour.
To find the number of hours, we divide the amount needed by the hourly wage:
\[ \text{Hours needed} = \frac{112}{14} \]
Calculating the above gives:
\[ \text{Hours needed} = 8 \]
Therefore, Christiana should work 8 hours to make the required amount after receiving the tip.