Finding the Third Proportional to 1,386.28 and 1,615.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.28 : 1,615.78 = 1,615.78 : x
2. Step 2: Convert to fraction form
   1,386.28/1,615.78 = 1,615.78/x
3. Step 3: Cross multiply
   1,386.28x = 1,615.78 × 1,615.78
4. Step 4: Simplify right side
   1,386.28x = 2,610,749.05
5. Step 5: Solve for x
   x = 2,610,749.05/1,386.28
6. Step 6: Final answer
   x = 1,883.28