Finding the Fourth Proportional to 13,147.44, 19,627.50 and 12,686.10

Step by Step Solution

1. Step 1: Write the proportion equation
   13,147.44 : 19,627.50 = 12,686.10 : x
2. Step 2: Convert to fraction form
   13,147.44/19,627.50 = 12,686.10/x
3. Step 3: Cross multiply
   13,147.44x = 19,627.50 × 12,686.10
4. Step 4: Simplify right side
   13,147.44x = 248,996,427.75
5. Step 5: Solve for x
   x = 248,996,427.75/13,147.44
6. Step 6: Final answer
   x = 18,938.78