Finding the Fourth Proportional to 21,828.61, 32,559.29 and 21,172.69

Step by Step Solution

1. Step 1: Write the proportion equation
   21,828.61 : 32,559.29 = 21,172.69 : x
2. Step 2: Convert to fraction form
   21,828.61/32,559.29 = 21,172.69/x
3. Step 3: Cross multiply
   21,828.61x = 32,559.29 × 21,172.69
4. Step 4: Simplify right side
   21,828.61x = 689,367,647.93
5. Step 5: Solve for x
   x = 689,367,647.93/21,828.61
6. Step 6: Final answer
   x = 31,580.92