Finding the Fourth Proportional to 1,638.80, 2,300.80 and 1,638.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,638.80 : 2,300.80 = 1,638.80 : x
2. Step 2: Convert to fraction form
   1,638.80/2,300.80 = 1,638.80/x
3. Step 3: Cross multiply
   1,638.80x = 2,300.80 × 1,638.80
4. Step 4: Simplify right side
   1,638.80x = 3,770,551.04
5. Step 5: Solve for x
   x = 3,770,551.04/1,638.80
6. Step 6: Final answer
   x = 2,300.80