Finding the Fourth Proportional to 21,990.96, 30,347.88 and 12,559.53

Step by Step Solution

1. Step 1: Write the proportion equation
   21,990.96 : 30,347.88 = 12,559.53 : x
2. Step 2: Convert to fraction form
   21,990.96/30,347.88 = 12,559.53/x
3. Step 3: Cross multiply
   21,990.96x = 30,347.88 × 12,559.53
4. Step 4: Simplify right side
   21,990.96x = 381,155,109.30
5. Step 5: Solve for x
   x = 381,155,109.30/21,990.96
6. Step 6: Final answer
   x = 17,332.35