Finding the Fourth Proportional to 156,211.55, 215,492.59 and 91,638.55

Step by Step Solution

1. Step 1: Write the proportion equation
   156,211.55 : 215,492.59 = 91,638.55 : x
2. Step 2: Convert to fraction form
   156,211.55/215,492.59 = 91,638.55/x
3. Step 3: Cross multiply
   156,211.55x = 215,492.59 × 91,638.55
4. Step 4: Simplify right side
   156,211.55x = 19,747,428,351.79
5. Step 5: Solve for x
   x = 19,747,428,351.79/156,211.55
6. Step 6: Final answer
   x = 126,414.65