Finding the Fourth Proportional to 142,061.20, 212,944.20 and 57,785.20

Step by Step Solution

1. Step 1: Write the proportion equation
   142,061.20 : 212,944.20 = 57,785.20 : x
2. Step 2: Convert to fraction form
   142,061.20/212,944.20 = 57,785.20/x
3. Step 3: Cross multiply
   142,061.20x = 212,944.20 × 57,785.20
4. Step 4: Simplify right side
   142,061.20x = 12,305,023,185.84
5. Step 5: Solve for x
   x = 12,305,023,185.84/142,061.20
6. Step 6: Final answer
   x = 86,617.76