Finding the Third Proportional to 66.60 and 145.30

Step by Step Solution

1. Step 1: Write the proportion equation
   66.60 : 145.30 = 145.30 : x
2. Step 2: Convert to fraction form
   66.60/145.30 = 145.30/x
3. Step 3: Cross multiply
   66.60x = 145.30 × 145.30
4. Step 4: Simplify right side
   66.60x = 21,112.32
5. Step 5: Solve for x
   x = 21,112.32/66.60
6. Step 6: Final answer
   x = 317.01