Finding the Third Proportional to 369.25 and 780.50

Step by Step Solution

1. Step 1: Write the proportion equation
   369.25 : 780.50 = 780.50 : x
2. Step 2: Convert to fraction form
   369.25/780.50 = 780.50/x
3. Step 3: Cross multiply
   369.25x = 780.50 × 780.50
4. Step 4: Simplify right side
   369.25x = 609,180.25
5. Step 5: Solve for x
   x = 609,180.25/369.25
6. Step 6: Final answer
   x = 1,649.78