Finding the Fourth Proportional to 12,641.81, 17,440.58 and 7,858.35

Step by Step Solution

1. Step 1: Write the proportion equation
   12,641.81 : 17,440.58 = 7,858.35 : x
2. Step 2: Convert to fraction form
   12,641.81/17,440.58 = 7,858.35/x
3. Step 3: Cross multiply
   12,641.81x = 17,440.58 × 7,858.35
4. Step 4: Simplify right side
   12,641.81x = 137,054,142.55
5. Step 5: Solve for x
   x = 137,054,142.55/12,641.81
6. Step 6: Final answer
   x = 10,841.34