Finding the Fourth Proportional to 100,212.72, 138,386.52 and 75,018.48

Step by Step Solution

1. Step 1: Write the proportion equation
   100,212.72 : 138,386.52 = 75,018.48 : x
2. Step 2: Convert to fraction form
   100,212.72/138,386.52 = 75,018.48/x
3. Step 3: Cross multiply
   100,212.72x = 138,386.52 × 75,018.48
4. Step 4: Simplify right side
   100,212.72x = 10,381,546,382.89
5. Step 5: Solve for x
   x = 10,381,546,382.89/100,212.72
6. Step 6: Final answer
   x = 103,595.10