Finding the Fourth Proportional to 93.50, 128.96 and 56.61

Step by Step Solution

1. Step 1: Write the proportion equation
   93.50 : 128.96 = 56.61 : x
2. Step 2: Convert to fraction form
   93.50/128.96 = 56.61/x
3. Step 3: Cross multiply
   93.50x = 128.96 × 56.61
4. Step 4: Simplify right side
   93.50x = 7,300.27
5. Step 5: Solve for x
   x = 7,300.27/93.50
6. Step 6: Final answer
   x = 78.08