Finding the Fourth Proportional to 12,780.50, 17,636.52 and 7,112.70

Step by Step Solution

1. Step 1: Write the proportion equation
   12,780.50 : 17,636.52 = 7,112.70 : x
2. Step 2: Convert to fraction form
   12,780.50/17,636.52 = 7,112.70/x
3. Step 3: Cross multiply
   12,780.50x = 17,636.52 × 7,112.70
4. Step 4: Simplify right side
   12,780.50x = 125,443,275.80
5. Step 5: Solve for x
   x = 125,443,275.80/12,780.50
6. Step 6: Final answer
   x = 9,815.21