Finding the Fourth Proportional to 76.61, 105.72 and 50.38

Step by Step Solution

1. Step 1: Write the proportion equation
   76.61 : 105.72 = 50.38 : x
2. Step 2: Convert to fraction form
   76.61/105.72 = 50.38/x
3. Step 3: Cross multiply
   76.61x = 105.72 × 50.38
4. Step 4: Simplify right side
   76.61x = 5,325.72
5. Step 5: Solve for x
   x = 5,325.72/76.61
6. Step 6: Final answer
   x = 69.52