Finding the Fourth Proportional to 81.98, 123.04 and 42.96

Step by Step Solution

1. Step 1: Write the proportion equation
   81.98 : 123.04 = 42.96 : x
2. Step 2: Convert to fraction form
   81.98/123.04 = 42.96/x
3. Step 3: Cross multiply
   81.98x = 123.04 × 42.96
4. Step 4: Simplify right side
   81.98x = 5,285.81
5. Step 5: Solve for x
   x = 5,285.81/81.98
6. Step 6: Final answer
   x = 64.48