Finding the Fourth Proportional to 21,930.72, 32,895.96 and 7,890.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,930.72 : 32,895.96 = 7,890.72 : x
2. Step 2: Convert to fraction form
   21,930.72/32,895.96 = 7,890.72/x
3. Step 3: Cross multiply
   21,930.72x = 32,895.96 × 7,890.72
4. Step 4: Simplify right side
   21,930.72x = 259,572,809.49
5. Step 5: Solve for x
   x = 259,572,809.49/21,930.72
6. Step 6: Final answer
   x = 11,836.04