Finding the Third Proportional to 278,457.75 and 434,322

Step by Step Solution

1. Step 1: Write the proportion equation
   278,457.75 : 434,322 = 434,322 : x
2. Step 2: Convert to fraction form
   278,457.75/434,322 = 434,322/x
3. Step 3: Cross multiply
   278,457.75x = 434,322 × 434,322
4. Step 4: Simplify right side
   278,457.75x = 188,635,599,684
5. Step 5: Solve for x
   x = 188,635,599,684/278,457.75
6. Step 6: Final answer
   x = 677,429.88