Finding the Fourth Proportional to 123.95, 185.72 and 78.18

Step by Step Solution

1. Step 1: Write the proportion equation
   123.95 : 185.72 = 78.18 : x
2. Step 2: Convert to fraction form
   123.95/185.72 = 78.18/x
3. Step 3: Cross multiply
   123.95x = 185.72 × 78.18
4. Step 4: Simplify right side
   123.95x = 14,519.20
5. Step 5: Solve for x
   x = 14,519.20/123.95
6. Step 6: Final answer
   x = 117.14