Finding the Fourth Proportional to 64,886.43, 89,501.93 and 57,210.06

Step by Step Solution

1. Step 1: Write the proportion equation
   64,886.43 : 89,501.93 = 57,210.06 : x
2. Step 2: Convert to fraction form
   64,886.43/89,501.93 = 57,210.06/x
3. Step 3: Cross multiply
   64,886.43x = 89,501.93 × 57,210.06
4. Step 4: Simplify right side
   64,886.43x = 5,120,410,499.37
5. Step 5: Solve for x
   x = 5,120,410,499.37/64,886.43
6. Step 6: Final answer
   x = 78,913.43