Finding the Fourth Proportional to 123.97, 185.89 and 42.78

Step by Step Solution

1. Step 1: Write the proportion equation
   123.97 : 185.89 = 42.78 : x
2. Step 2: Convert to fraction form
   123.97/185.89 = 42.78/x
3. Step 3: Cross multiply
   123.97x = 185.89 × 42.78
4. Step 4: Simplify right side
   123.97x = 7,952.37
5. Step 5: Solve for x
   x = 7,952.37/123.97
6. Step 6: Final answer
   x = 64.15