Finding the Fourth Proportional to 13,139.67, 18,131.98 and 7,475.79

Step by Step Solution

1. Step 1: Write the proportion equation
   13,139.67 : 18,131.98 = 7,475.79 : x
2. Step 2: Convert to fraction form
   13,139.67/18,131.98 = 7,475.79/x
3. Step 3: Cross multiply
   13,139.67x = 18,131.98 × 7,475.79
4. Step 4: Simplify right side
   13,139.67x = 135,550,874.76
5. Step 5: Solve for x
   x = 135,550,874.76/13,139.67
6. Step 6: Final answer
   x = 10,316.16