Finding the Fourth Proportional to 85,419.39, 128,056.17 and 60,380.67

Step by Step Solution

1. Step 1: Write the proportion equation
   85,419.39 : 128,056.17 = 60,380.67 : x
2. Step 2: Convert to fraction form
   85,419.39/128,056.17 = 60,380.67/x
3. Step 3: Cross multiply
   85,419.39x = 128,056.17 × 60,380.67
4. Step 4: Simplify right side
   85,419.39x = 7,732,118,048.87
5. Step 5: Solve for x
   x = 7,732,118,048.87/85,419.39
6. Step 6: Final answer
   x = 90,519.47