Finding the Fourth Proportional to 78.43, 108.18 and 53.56

Step by Step Solution

1. Step 1: Write the proportion equation
   78.43 : 108.18 = 53.56 : x
2. Step 2: Convert to fraction form
   78.43/108.18 = 53.56/x
3. Step 3: Cross multiply
   78.43x = 108.18 × 53.56
4. Step 4: Simplify right side
   78.43x = 5,794.12
5. Step 5: Solve for x
   x = 5,794.12/78.43
6. Step 6: Final answer
   x = 73.88