Finding the Fourth Proportional to 71,705.76, 98,946.72 and 39,871.68

Step by Step Solution

1. Step 1: Write the proportion equation
   71,705.76 : 98,946.72 = 39,871.68 : x
2. Step 2: Convert to fraction form
   71,705.76/98,946.72 = 39,871.68/x
3. Step 3: Cross multiply
   71,705.76x = 98,946.72 × 39,871.68
4. Step 4: Simplify right side
   71,705.76x = 3,945,171,956.89
5. Step 5: Solve for x
   x = 3,945,171,956.89/71,705.76
6. Step 6: Final answer
   x = 55,018.90