Finding the Fourth Proportional to 39,069.90, 53,916.72 and 21,164.91

Step by Step Solution

1. Step 1: Write the proportion equation
   39,069.90 : 53,916.72 = 21,164.91 : x
2. Step 2: Convert to fraction form
   39,069.90/53,916.72 = 21,164.91/x
3. Step 3: Cross multiply
   39,069.90x = 53,916.72 × 21,164.91
4. Step 4: Simplify right side
   39,069.90x = 1,141,142,526.30
5. Step 5: Solve for x
   x = 1,141,142,526.30/39,069.90
6. Step 6: Final answer
   x = 29,207.72