Finding the Fourth Proportional to 100.23, 138.24 and 72.69

Step by Step Solution

1. Step 1: Write the proportion equation
   100.23 : 138.24 = 72.69 : x
2. Step 2: Convert to fraction form
   100.23/138.24 = 72.69/x
3. Step 3: Cross multiply
   100.23x = 138.24 × 72.69
4. Step 4: Simplify right side
   100.23x = 10,048.67
5. Step 5: Solve for x
   x = 10,048.67/100.23
6. Step 6: Final answer
   x = 100.26