Finding the Fourth Proportional to 5,715.91, 7,870.42 and 5,003.77

Step by Step Solution

1. Step 1: Write the proportion equation
   5,715.91 : 7,870.42 = 5,003.77 : x
2. Step 2: Convert to fraction form
   5,715.91/7,870.42 = 5,003.77/x
3. Step 3: Cross multiply
   5,715.91x = 7,870.42 × 5,003.77
4. Step 4: Simplify right side
   5,715.91x = 39,381,771.48
5. Step 5: Solve for x
   x = 39,381,771.48/5,715.91
6. Step 6: Final answer
   x = 6,889.85