Finding the Fourth Proportional to 91,978.61, 126,941.82 and 51,691.50

Step by Step Solution

1. Step 1: Write the proportion equation
   91,978.61 : 126,941.82 = 51,691.50 : x
2. Step 2: Convert to fraction form
   91,978.61/126,941.82 = 51,691.50/x
3. Step 3: Cross multiply
   91,978.61x = 126,941.82 × 51,691.50
4. Step 4: Simplify right side
   91,978.61x = 6,561,812,894.69
5. Step 5: Solve for x
   x = 6,561,812,894.69/91,978.61
6. Step 6: Final answer
   x = 71,340.64