Finding the Fourth Proportional to 31,120.61, 42,602.85 and 30,898.26

Step by Step Solution

1. Step 1: Write the proportion equation
   31,120.61 : 42,602.85 = 30,898.26 : x
2. Step 2: Convert to fraction form
   31,120.61/42,602.85 = 30,898.26/x
3. Step 3: Cross multiply
   31,120.61x = 42,602.85 × 30,898.26
4. Step 4: Simplify right side
   31,120.61x = 1,316,353,936.04
5. Step 5: Solve for x
   x = 1,316,353,936.04/31,120.61
6. Step 6: Final answer
   x = 42,298.47