Finding the Fourth Proportional to 64,971.90, 89,461.35 and 55,390.41

Step by Step Solution

1. Step 1: Write the proportion equation
   64,971.90 : 89,461.35 = 55,390.41 : x
2. Step 2: Convert to fraction form
   64,971.90/89,461.35 = 55,390.41/x
3. Step 3: Cross multiply
   64,971.90x = 89,461.35 × 55,390.41
4. Step 4: Simplify right side
   64,971.90x = 4,955,300,855.65
5. Step 5: Solve for x
   x = 4,955,300,855.65/64,971.90
6. Step 6: Final answer
   x = 76,268.37