Finding the Fourth Proportional to 78.22, 107.89 and 53.65

Step by Step Solution

1. Step 1: Write the proportion equation
   78.22 : 107.89 = 53.65 : x
2. Step 2: Convert to fraction form
   78.22/107.89 = 53.65/x
3. Step 3: Cross multiply
   78.22x = 107.89 × 53.65
4. Step 4: Simplify right side
   78.22x = 5,788.30
5. Step 5: Solve for x
   x = 5,788.30/78.22
6. Step 6: Final answer
   x = 74.00