Finding the Fourth Proportional to 78.39, 108.12 and 53.82

Step by Step Solution

1. Step 1: Write the proportion equation
   78.39 : 108.12 = 53.82 : x
2. Step 2: Convert to fraction form
   78.39/108.12 = 53.82/x
3. Step 3: Cross multiply
   78.39x = 108.12 × 53.82
4. Step 4: Simplify right side
   78.39x = 5,819.02
5. Step 5: Solve for x
   x = 5,819.02/78.39
6. Step 6: Final answer
   x = 74.23