Finding the Fourth Proportional to 85,429.53, 128,071.37 and 60,390.81

Step by Step Solution

1. Step 1: Write the proportion equation
   85,429.53 : 128,071.37 = 60,390.81 : x
2. Step 2: Convert to fraction form
   85,429.53/128,071.37 = 60,390.81/x
3. Step 3: Cross multiply
   85,429.53x = 128,071.37 × 60,390.81
4. Step 4: Simplify right side
   85,429.53x = 7,734,333,470.16
5. Step 5: Solve for x
   x = 7,734,333,470.16/85,429.53
6. Step 6: Final answer
   x = 90,534.66