Finding the Fourth Proportional to 76.83, 115.82 and 72.42

Step by Step Solution

1. Step 1: Write the proportion equation
   76.83 : 115.82 = 72.42 : x
2. Step 2: Convert to fraction form
   76.83/115.82 = 72.42/x
3. Step 3: Cross multiply
   76.83x = 115.82 × 72.42
4. Step 4: Simplify right side
   76.83x = 8,387.32
5. Step 5: Solve for x
   x = 8,387.32/76.83
6. Step 6: Final answer
   x = 109.17