Finding the Fourth Proportional to 78.57, 117.69 and 76.55

Step by Step Solution

1. Step 1: Write the proportion equation
   78.57 : 117.69 = 76.55 : x
2. Step 2: Convert to fraction form
   78.57/117.69 = 76.55/x
3. Step 3: Cross multiply
   78.57x = 117.69 × 76.55
4. Step 4: Simplify right side
   78.57x = 9,008.29
5. Step 5: Solve for x
   x = 9,008.29/78.57
6. Step 6: Final answer
   x = 114.65