Finding the Fourth Proportional to 91,395.72, 136,714.50 and 85,797

Step by Step Solution

1. Step 1: Write the proportion equation
   91,395.72 : 136,714.50 = 85,797 : x
2. Step 2: Convert to fraction form
   91,395.72/136,714.50 = 85,797/x
3. Step 3: Cross multiply
   91,395.72x = 136,714.50 × 85,797
4. Step 4: Simplify right side
   91,395.72x = 11,729,693,956.50
5. Step 5: Solve for x
   x = 11,729,693,956.50/91,395.72
6. Step 6: Final answer
   x = 128,339.64