Finding the Fourth Proportional to 78,121.71, 107,807.91 and 42,311.72

Step by Step Solution

1. Step 1: Write the proportion equation
   78,121.71 : 107,807.91 = 42,311.72 : x
2. Step 2: Convert to fraction form
   78,121.71/107,807.91 = 42,311.72/x
3. Step 3: Cross multiply
   78,121.71x = 107,807.91 × 42,311.72
4. Step 4: Simplify right side
   78,121.71x = 4,561,538,101.71
5. Step 5: Solve for x
   x = 4,561,538,101.71/78,121.71
6. Step 6: Final answer
   x = 58,390.15