Finding the Fourth Proportional to 31,085.49, 42,904.61 and 20,476.05

Step by Step Solution

1. Step 1: Write the proportion equation
   31,085.49 : 42,904.61 = 20,476.05 : x
2. Step 2: Convert to fraction form
   31,085.49/42,904.61 = 20,476.05/x
3. Step 3: Cross multiply
   31,085.49x = 42,904.61 × 20,476.05
4. Step 4: Simplify right side
   31,085.49x = 878,516,837.21
5. Step 5: Solve for x
   x = 878,516,837.21/31,085.49
6. Step 6: Final answer
   x = 28,261.32