Finding the Fourth Proportional to 100.41, 138.51 and 72.82

Step by Step Solution

1. Step 1: Write the proportion equation
   100.41 : 138.51 = 72.82 : x
2. Step 2: Convert to fraction form
   100.41/138.51 = 72.82/x
3. Step 3: Cross multiply
   100.41x = 138.51 × 72.82
4. Step 4: Simplify right side
   100.41x = 10,085.69
5. Step 5: Solve for x
   x = 10,085.69/100.41
6. Step 6: Final answer
   x = 100.45