Finding the Fourth Proportional to 78.52, 107.69 and 76.72

Step by Step Solution

1. Step 1: Write the proportion equation
   78.52 : 107.69 = 76.72 : x
2. Step 2: Convert to fraction form
   78.52/107.69 = 76.72/x
3. Step 3: Cross multiply
   78.52x = 107.69 × 76.72
4. Step 4: Simplify right side
   78.52x = 8,261.98
5. Step 5: Solve for x
   x = 8,261.98/78.52
6. Step 6: Final answer
   x = 105.22