Finding the Third Proportional to 379.31 and 830.91

Step by Step Solution

1. Step 1: Write the proportion equation
   379.31 : 830.91 = 830.91 : x
2. Step 2: Convert to fraction form
   379.31/830.91 = 830.91/x
3. Step 3: Cross multiply
   379.31x = 830.91 × 830.91
4. Step 4: Simplify right side
   379.31x = 690,405.20
5. Step 5: Solve for x
   x = 690,405.20/379.31
6. Step 6: Final answer
   x = 1,820.15