Finding the Fourth Proportional to 31,592.79, 43,615.78 and 21,916.35

Step by Step Solution

1. Step 1: Write the proportion equation
   31,592.79 : 43,615.78 = 21,916.35 : x
2. Step 2: Convert to fraction form
   31,592.79/43,615.78 = 21,916.35/x
3. Step 3: Cross multiply
   31,592.79x = 43,615.78 × 21,916.35
4. Step 4: Simplify right side
   31,592.79x = 955,898,645.21
5. Step 5: Solve for x
   x = 955,898,645.21/31,592.79
6. Step 6: Final answer
   x = 30,256.86