Finding the Fourth Proportional to 128.56, 191.86 and 124.56

Step by Step Solution

1. Step 1: Write the proportion equation
   128.56 : 191.86 = 124.56 : x
2. Step 2: Convert to fraction form
   128.56/191.86 = 124.56/x
3. Step 3: Cross multiply
   128.56x = 191.86 × 124.56
4. Step 4: Simplify right side
   128.56x = 23,898.08
5. Step 5: Solve for x
   x = 23,898.08/128.56
6. Step 6: Final answer
   x = 185.89