Finding the Fourth Proportional to 128,499.08, 191,828.91 and 111,688.57

Step by Step Solution

1. Step 1: Write the proportion equation
   128,499.08 : 191,828.91 = 111,688.57 : x
2. Step 2: Convert to fraction form
   128,499.08/191,828.91 = 111,688.57/x
3. Step 3: Cross multiply
   128,499.08x = 191,828.91 × 111,688.57
4. Step 4: Simplify right side
   128,499.08x = 21,425,096,672.93
5. Step 5: Solve for x
   x = 21,425,096,672.93/128,499.08
6. Step 6: Final answer
   x = 166,733.46