Finding the Fourth Proportional to 78.49, 108.23 and 53.21

Step by Step Solution

1. Step 1: Write the proportion equation
   78.49 : 108.23 = 53.21 : x
2. Step 2: Convert to fraction form
   78.49/108.23 = 53.21/x
3. Step 3: Cross multiply
   78.49x = 108.23 × 53.21
4. Step 4: Simplify right side
   78.49x = 5,758.38
5. Step 5: Solve for x
   x = 5,758.38/78.49
6. Step 6: Final answer
   x = 73.37