Finding the Third Proportional to 187.31 and 379.69

Step by Step Solution

1. Step 1: Write the proportion equation
   187.31 : 379.69 = 379.69 : x
2. Step 2: Convert to fraction form
   187.31/379.69 = 379.69/x
3. Step 3: Cross multiply
   187.31x = 379.69 × 379.69
4. Step 4: Simplify right side
   187.31x = 144,162.60
5. Step 5: Solve for x
   x = 144,162.60/187.31
6. Step 6: Final answer
   x = 769.64