Finding the Fourth Proportional to 12,903.72, 17,810.32 and 7,870.70

Step by Step Solution

1. Step 1: Write the proportion equation
   12,903.72 : 17,810.32 = 7,870.70 : x
2. Step 2: Convert to fraction form
   12,903.72/17,810.32 = 7,870.70/x
3. Step 3: Cross multiply
   12,903.72x = 17,810.32 × 7,870.70
4. Step 4: Simplify right side
   12,903.72x = 140,179,685.62
5. Step 5: Solve for x
   x = 140,179,685.62/12,903.72
6. Step 6: Final answer
   x = 10,863.51