Finding the Fourth Proportional to 13,312.16, 18,371.62 and 7,648.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13,312.16 : 18,371.62 = 7,648.72 : x
2. Step 2: Convert to fraction form
   13,312.16/18,371.62 = 7,648.72/x
3. Step 3: Cross multiply
   13,312.16x = 18,371.62 × 7,648.72
4. Step 4: Simplify right side
   13,312.16x = 140,519,377.33
5. Step 5: Solve for x
   x = 140,519,377.33/13,312.16
6. Step 6: Final answer
   x = 10,555.72