Finding the Fourth Proportional to 10,513.61, 14,509.80 and 7,856.40

Step by Step Solution

1. Step 1: Write the proportion equation
   10,513.61 : 14,509.80 = 7,856.40 : x
2. Step 2: Convert to fraction form
   10,513.61/14,509.80 = 7,856.40/x
3. Step 3: Cross multiply
   10,513.61x = 14,509.80 × 7,856.40
4. Step 4: Simplify right side
   10,513.61x = 113,994,792.72
5. Step 5: Solve for x
   x = 113,994,792.72/10,513.61
6. Step 6: Final answer
   x = 10,842.60