Finding the Fourth Proportional to 64,890.80, 89,517.12 and 41,912.72

Step by Step Solution

1. Step 1: Write the proportion equation
   64,890.80 : 89,517.12 = 41,912.72 : x
2. Step 2: Convert to fraction form
   64,890.80/89,517.12 = 41,912.72/x
3. Step 3: Cross multiply
   64,890.80x = 89,517.12 × 41,912.72
4. Step 4: Simplify right side
   64,890.80x = 3,751,905,985.77
5. Step 5: Solve for x
   x = 3,751,905,985.77/64,890.80
6. Step 6: Final answer
   x = 57,818.77