Finding the Fourth Proportional to 72,100.61, 99,545.64 and 64,533.80

Step by Step Solution

1. Step 1: Write the proportion equation
   72,100.61 : 99,545.64 = 64,533.80 : x
2. Step 2: Convert to fraction form
   72,100.61/99,545.64 = 64,533.80/x
3. Step 3: Cross multiply
   72,100.61x = 99,545.64 × 64,533.80
4. Step 4: Simplify right side
   72,100.61x = 6,424,058,422.63
5. Step 5: Solve for x
   x = 6,424,058,422.63/72,100.61
6. Step 6: Final answer
   x = 89,098.53