Finding the Third Proportional to 985.50 and 2,109

Step by Step Solution

1. Step 1: Write the proportion equation
   985.50 : 2,109 = 2,109 : x
2. Step 2: Convert to fraction form
   985.50/2,109 = 2,109/x
3. Step 3: Cross multiply
   985.50x = 2,109 × 2,109
4. Step 4: Simplify right side
   985.50x = 4,447,881
5. Step 5: Solve for x
   x = 4,447,881/985.50
6. Step 6: Final answer
   x = 4,513.32