Finding the Third Proportional to 1,688.50 and 1,931.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,688.50 : 1,931.50 = 1,931.50 : x
2. Step 2: Convert to fraction form
   1,688.50/1,931.50 = 1,931.50/x
3. Step 3: Cross multiply
   1,688.50x = 1,931.50 × 1,931.50
4. Step 4: Simplify right side
   1,688.50x = 3,730,692.25
5. Step 5: Solve for x
   x = 3,730,692.25/1,688.50
6. Step 6: Final answer
   x = 2,209.47