Finding the Fourth Proportional to 427,022.38, 640,611.42 and 142,685.86

Step by Step Solution

1. Step 1: Write the proportion equation
   427,022.38 : 640,611.42 = 142,685.86 : x
2. Step 2: Convert to fraction form
   427,022.38/640,611.42 = 142,685.86/x
3. Step 3: Cross multiply
   427,022.38x = 640,611.42 × 142,685.86
4. Step 4: Simplify right side
   427,022.38x = 91,406,191,388.52
5. Step 5: Solve for x
   x = 91,406,191,388.52/427,022.38
6. Step 6: Final answer
   x = 214,054.80