Finding the Fourth Proportional to 124.31, 171.56 and 72.56

Step by Step Solution

1. Step 1: Write the proportion equation
   124.31 : 171.56 = 72.56 : x
2. Step 2: Convert to fraction form
   124.31/171.56 = 72.56/x
3. Step 3: Cross multiply
   124.31x = 171.56 × 72.56
4. Step 4: Simplify right side
   124.31x = 12,449.00
5. Step 5: Solve for x
   x = 12,449.00/124.31
6. Step 6: Final answer
   x = 100.14