Finding the Fourth Proportional to 100.76, 139.01 and 59.28

Step by Step Solution

1. Step 1: Write the proportion equation
   100.76 : 139.01 = 59.28 : x
2. Step 2: Convert to fraction form
   100.76/139.01 = 59.28/x
3. Step 3: Cross multiply
   100.76x = 139.01 × 59.28
4. Step 4: Simplify right side
   100.76x = 8,240.22
5. Step 5: Solve for x
   x = 8,240.22/100.76
6. Step 6: Final answer
   x = 81.78