Finding the Fourth Proportional to 123.91, 185.90 and 42.77

Step by Step Solution

1. Step 1: Write the proportion equation
   123.91 : 185.90 = 42.77 : x
2. Step 2: Convert to fraction form
   123.91/185.90 = 42.77/x
3. Step 3: Cross multiply
   123.91x = 185.90 × 42.77
4. Step 4: Simplify right side
   123.91x = 7,951.19
5. Step 5: Solve for x
   x = 7,951.19/123.91
6. Step 6: Final answer
   x = 64.17