Finding the Fourth Proportional to 118,218.72, 163,138.62 and 64,503.72

Step by Step Solution

1. Step 1: Write the proportion equation
   118,218.72 : 163,138.62 = 64,503.72 : x
2. Step 2: Convert to fraction form
   118,218.72/163,138.62 = 64,503.72/x
3. Step 3: Cross multiply
   118,218.72x = 163,138.62 × 64,503.72
4. Step 4: Simplify right side
   118,218.72x = 10,523,047,865.67
5. Step 5: Solve for x
   x = 10,523,047,865.67/118,218.72
6. Step 6: Final answer
   x = 89,013.38