Finding the Fourth Proportional to 72.72, 100.21 and 57.93

Step by Step Solution

1. Step 1: Write the proportion equation
   72.72 : 100.21 = 57.93 : x
2. Step 2: Convert to fraction form
   72.72/100.21 = 57.93/x
3. Step 3: Cross multiply
   72.72x = 100.21 × 57.93
4. Step 4: Simplify right side
   72.72x = 5,805.17
5. Step 5: Solve for x
   x = 5,805.17/72.72
6. Step 6: Final answer
   x = 79.83