Finding the Fourth Proportional to 12,685.60, 17,505.56 and 7,020.56

Step by Step Solution

1. Step 1: Write the proportion equation
   12,685.60 : 17,505.56 = 7,020.56 : x
2. Step 2: Convert to fraction form
   12,685.60/17,505.56 = 7,020.56/x
3. Step 3: Cross multiply
   12,685.60x = 17,505.56 × 7,020.56
4. Step 4: Simplify right side
   12,685.60x = 122,898,834.31
5. Step 5: Solve for x
   x = 122,898,834.31/12,685.60
6. Step 6: Final answer
   x = 9,688.06