Finding the Third Proportional to 870.61 and 1,862.72

Step by Step Solution

1. Step 1: Write the proportion equation
   870.61 : 1,862.72 = 1,862.72 : x
2. Step 2: Convert to fraction form
   870.61/1,862.72 = 1,862.72/x
3. Step 3: Cross multiply
   870.61x = 1,862.72 × 1,862.72
4. Step 4: Simplify right side
   870.61x = 3,469,721.14
5. Step 5: Solve for x
   x = 3,469,721.14/870.61
6. Step 6: Final answer
   x = 3,985.39