Finding the Third Proportional to 145.75 and 212.50

Step by Step Solution

1. Step 1: Write the proportion equation
   145.75 : 212.50 = 212.50 : x
2. Step 2: Convert to fraction form
   145.75/212.50 = 212.50/x
3. Step 3: Cross multiply
   145.75x = 212.50 × 212.50
4. Step 4: Simplify right side
   145.75x = 45,156.25
5. Step 5: Solve for x
   x = 45,156.25/145.75
6. Step 6: Final answer
   x = 309.82