Finding the Fourth Proportional to 7,856.10, 10,838.72 and 4,870.86

Step by Step Solution

1. Step 1: Write the proportion equation
   7,856.10 : 10,838.72 = 4,870.86 : x
2. Step 2: Convert to fraction form
   7,856.10/10,838.72 = 4,870.86/x
3. Step 3: Cross multiply
   7,856.10x = 10,838.72 × 4,870.86
4. Step 4: Simplify right side
   7,856.10x = 52,793,887.70
5. Step 5: Solve for x
   x = 52,793,887.70/7,856.10
6. Step 6: Final answer
   x = 6,720.11