Finding the Fourth Proportional to 139,018.72, 208,542.66 and 45,531.76

Step by Step Solution

1. Step 1: Write the proportion equation
   139,018.72 : 208,542.66 = 45,531.76 : x
2. Step 2: Convert to fraction form
   139,018.72/208,542.66 = 45,531.76/x
3. Step 3: Cross multiply
   139,018.72x = 208,542.66 × 45,531.76
4. Step 4: Simplify right side
   139,018.72x = 9,495,314,344.88
5. Step 5: Solve for x
   x = 9,495,314,344.88/139,018.72
6. Step 6: Final answer
   x = 68,302.42