Finding the Fourth Proportional to 114.84, 171.96 and 78.72

Step by Step Solution

1. Step 1: Write the proportion equation
   114.84 : 171.96 = 78.72 : x
2. Step 2: Convert to fraction form
   114.84/171.96 = 78.72/x
3. Step 3: Cross multiply
   114.84x = 171.96 × 78.72
4. Step 4: Simplify right side
   114.84x = 13,536.69
5. Step 5: Solve for x
   x = 13,536.69/114.84
6. Step 6: Final answer
   x = 117.87