Finding the Fourth Proportional to 11,890.72, 16,411.92 and 7,912

Step by Step Solution

1. Step 1: Write the proportion equation
   11,890.72 : 16,411.92 = 7,912 : x
2. Step 2: Convert to fraction form
   11,890.72/16,411.92 = 7,912/x
3. Step 3: Cross multiply
   11,890.72x = 16,411.92 × 7,912
4. Step 4: Simplify right side
   11,890.72x = 129,851,111.04
5. Step 5: Solve for x
   x = 129,851,111.04/11,890.72
6. Step 6: Final answer
   x = 10,920.37