Finding the Fourth Proportional to 11,279.62, 16,890.27 and 7,780.42

Step by Step Solution

1. Step 1: Write the proportion equation
   11,279.62 : 16,890.27 = 7,780.42 : x
2. Step 2: Convert to fraction form
   11,279.62/16,890.27 = 7,780.42/x
3. Step 3: Cross multiply
   11,279.62x = 16,890.27 × 7,780.42
4. Step 4: Simplify right side
   11,279.62x = 131,413,394.51
5. Step 5: Solve for x
   x = 131,413,394.51/11,279.62
6. Step 6: Final answer
   x = 11,650.52