Finding the Third Proportional to 688.50 and 1,128

Step by Step Solution

1. Step 1: Write the proportion equation
   688.50 : 1,128 = 1,128 : x
2. Step 2: Convert to fraction form
   688.50/1,128 = 1,128/x
3. Step 3: Cross multiply
   688.50x = 1,128 × 1,128
4. Step 4: Simplify right side
   688.50x = 1,272,384
5. Step 5: Solve for x
   x = 1,272,384/688.50
6. Step 6: Final answer
   x = 1,848.05