Finding the Third Proportional to 1,275.38 and 1,678.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,275.38 : 1,678.69 = 1,678.69 : x
2. Step 2: Convert to fraction form
   1,275.38/1,678.69 = 1,678.69/x
3. Step 3: Cross multiply
   1,275.38x = 1,678.69 × 1,678.69
4. Step 4: Simplify right side
   1,275.38x = 2,817,991.72
5. Step 5: Solve for x
   x = 2,817,991.72/1,275.38
6. Step 6: Final answer
   x = 2,209.54