Finding the Fourth Proportional to 31,088.11, 42,886.83 and 21,020.02

Step by Step Solution

1. Step 1: Write the proportion equation
   31,088.11 : 42,886.83 = 21,020.02 : x
2. Step 2: Convert to fraction form
   31,088.11/42,886.83 = 21,020.02/x
3. Step 3: Cross multiply
   31,088.11x = 42,886.83 × 21,020.02
4. Step 4: Simplify right side
   31,088.11x = 901,482,024.34
5. Step 5: Solve for x
   x = 901,482,024.34/31,088.11
6. Step 6: Final answer
   x = 28,997.65