Finding the Fourth Proportional to 100.73, 139.01 and 56.47

Step by Step Solution

1. Step 1: Write the proportion equation
   100.73 : 139.01 = 56.47 : x
2. Step 2: Convert to fraction form
   100.73/139.01 = 56.47/x
3. Step 3: Cross multiply
   100.73x = 139.01 × 56.47
4. Step 4: Simplify right side
   100.73x = 7,849.96
5. Step 5: Solve for x
   x = 7,849.96/100.73
6. Step 6: Final answer
   x = 77.93