Finding the Fourth Proportional to 72.55, 108.78 and 29.21

Step by Step Solution

1. Step 1: Write the proportion equation
   72.55 : 108.78 = 29.21 : x
2. Step 2: Convert to fraction form
   72.55/108.78 = 29.21/x
3. Step 3: Cross multiply
   72.55x = 108.78 × 29.21
4. Step 4: Simplify right side
   72.55x = 3,177.32
5. Step 5: Solve for x
   x = 3,177.32/72.55
6. Step 6: Final answer
   x = 43.80