Finding the Fourth Proportional to 65.25, 89.76 and 57.42

Step by Step Solution

1. Step 1: Write the proportion equation
   65.25 : 89.76 = 57.42 : x
2. Step 2: Convert to fraction form
   65.25/89.76 = 57.42/x
3. Step 3: Cross multiply
   65.25x = 89.76 × 57.42
4. Step 4: Simplify right side
   65.25x = 5,154.02
5. Step 5: Solve for x
   x = 5,154.02/65.25
6. Step 6: Final answer
   x = 78.99