Final answer:
After dividing the total investment of $51,000 by the sum of the ratio parts (17), we determine one part is worth $3,000. Multiplying this by the number of parts attributed to Julie and Kristain gives us their individual investments: Julie invested $15,000, and Kristain invested $36,000.
Step-by-step explanation:
To find out how much Julie and Kristain invested, we need to calculate their individual contributions based on the ratio 5:12. Together, they need a total of $51,000 for the business. To find out the value of one part of the ratio, we divide the total amount of investment by the sum of the ratio parts:
5 parts + 12 parts = 17 parts
Julie and Kristain's total investment: $51,000
Value of one part: $51,000 ÷ 17 = $3,000
Now, we multiply the value of one part by the number of parts each person has:
- Julie's investment: 5 parts × $3,000 = $15,000
- Kristain's investment: 12 parts × $3,000 = $36,000
Hence, the correct answer is option C: Julie invested $15,000 and Kristain invested $36,000.