Finding the Third Proportional to 178.45 and 278.86

Step by Step Solution

1. Step 1: Write the proportion equation
   178.45 : 278.86 = 278.86 : x
2. Step 2: Convert to fraction form
   178.45/278.86 = 278.86/x
3. Step 3: Cross multiply
   178.45x = 278.86 × 278.86
4. Step 4: Simplify right side
   178.45x = 77,762.55
5. Step 5: Solve for x
   x = 77,762.55/178.45
6. Step 6: Final answer
   x = 435.76