Finding the Third Proportional to 190,112 and 278,256

Step by Step Solution

1. Step 1: Write the proportion equation
   190,112 : 278,256 = 278,256 : x
2. Step 2: Convert to fraction form
   190,112/278,256 = 278,256/x
3. Step 3: Cross multiply
   190,112x = 278,256 × 278,256
4. Step 4: Simplify right side
   190,112x = 77,426,401,536
5. Step 5: Solve for x
   x = 77,426,401,536/190,112
6. Step 6: Final answer
   x = 407,267.30