Finding the Third Proportional to 818 and 1,256.50

Step by Step Solution

1. Step 1: Write the proportion equation
   818 : 1,256.50 = 1,256.50 : x
2. Step 2: Convert to fraction form
   818/1,256.50 = 1,256.50/x
3. Step 3: Cross multiply
   818x = 1,256.50 × 1,256.50
4. Step 4: Simplify right side
   818x = 1,578,792.25
5. Step 5: Solve for x
   x = 1,578,792.25/818
6. Step 6: Final answer
   x = 1,930.06