Finding the Third Proportional to 1,638.75 and 3,580.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,638.75 : 3,580.50 = 3,580.50 : x
2. Step 2: Convert to fraction form
   1,638.75/3,580.50 = 3,580.50/x
3. Step 3: Cross multiply
   1,638.75x = 3,580.50 × 3,580.50
4. Step 4: Simplify right side
   1,638.75x = 12,819,980.25
5. Step 5: Solve for x
   x = 12,819,980.25/1,638.75
6. Step 6: Final answer
   x = 7,823.02