Finding the Fourth Proportional to 78.06, 107.71 and 53.12

Step by Step Solution

1. Step 1: Write the proportion equation
   78.06 : 107.71 = 53.12 : x
2. Step 2: Convert to fraction form
   78.06/107.71 = 53.12/x
3. Step 3: Cross multiply
   78.06x = 107.71 × 53.12
4. Step 4: Simplify right side
   78.06x = 5,721.56
5. Step 5: Solve for x
   x = 5,721.56/78.06
6. Step 6: Final answer
   x = 73.30