Finding the Fourth Proportional to 1,980.48, 2,729.77 and 1,389.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,980.48 : 2,729.77 = 1,389.99 : x
2. Step 2: Convert to fraction form
   1,980.48/2,729.77 = 1,389.99/x
3. Step 3: Cross multiply
   1,980.48x = 2,729.77 × 1,389.99
4. Step 4: Simplify right side
   1,980.48x = 3,794,353.00
5. Step 5: Solve for x
   x = 3,794,353.00/1,980.48
6. Step 6: Final answer
   x = 1,915.88