Finding the Third Proportional to 621 and 1,009.50

Step by Step Solution

1. Step 1: Write the proportion equation
   621 : 1,009.50 = 1,009.50 : x
2. Step 2: Convert to fraction form
   621/1,009.50 = 1,009.50/x
3. Step 3: Cross multiply
   621x = 1,009.50 × 1,009.50
4. Step 4: Simplify right side
   621x = 1,019,090.25
5. Step 5: Solve for x
   x = 1,019,090.25/621
6. Step 6: Final answer
   x = 1,641.05