Finding the Fourth Proportional to 64,101.76, 87,989.60 and 56,870.08

Step by Step Solution

1. Step 1: Write the proportion equation
   64,101.76 : 87,989.60 = 56,870.08 : x
2. Step 2: Convert to fraction form
   64,101.76/87,989.60 = 56,870.08/x
3. Step 3: Cross multiply
   64,101.76x = 87,989.60 × 56,870.08
4. Step 4: Simplify right side
   64,101.76x = 5,003,975,591.17
5. Step 5: Solve for x
   x = 5,003,975,591.17/64,101.76
6. Step 6: Final answer
   x = 78,063.00