Finding the Fourth Proportional to 31,094.72, 42,876.83 and 21,005.65

Step by Step Solution

1. Step 1: Write the proportion equation
   31,094.72 : 42,876.83 = 21,005.65 : x
2. Step 2: Convert to fraction form
   31,094.72/42,876.83 = 21,005.65/x
3. Step 3: Cross multiply
   31,094.72x = 42,876.83 × 21,005.65
4. Step 4: Simplify right side
   31,094.72x = 900,655,364.68
5. Step 5: Solve for x
   x = 900,655,364.68/31,094.72
6. Step 6: Final answer
   x = 28,964.90