Finding the Third Proportional to 1,298.11 and 2,780.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,298.11 : 2,780.79 = 2,780.79 : x
2. Step 2: Convert to fraction form
   1,298.11/2,780.79 = 2,780.79/x
3. Step 3: Cross multiply
   1,298.11x = 2,780.79 × 2,780.79
4. Step 4: Simplify right side
   1,298.11x = 7,732,787.81
5. Step 5: Solve for x
   x = 7,732,787.81/1,298.11
6. Step 6: Final answer
   x = 5,956.96