Finding the Third Proportional to 316 and 666.50

Step by Step Solution

1. Step 1: Write the proportion equation
   316 : 666.50 = 666.50 : x
2. Step 2: Convert to fraction form
   316/666.50 = 666.50/x
3. Step 3: Cross multiply
   316x = 666.50 × 666.50
4. Step 4: Simplify right side
   316x = 444,222.25
5. Step 5: Solve for x
   x = 444,222.25/316
6. Step 6: Final answer
   x = 1,405.77