Finding the Fourth Proportional to 1,978.60, 2,729.61 and 1,192.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.60 : 2,729.61 = 1,192.20 : x
2. Step 2: Convert to fraction form
   1,978.60/2,729.61 = 1,192.20/x
3. Step 3: Cross multiply
   1,978.60x = 2,729.61 × 1,192.20
4. Step 4: Simplify right side
   1,978.60x = 3,254,241.04
5. Step 5: Solve for x
   x = 3,254,241.04/1,978.60
6. Step 6: Final answer
   x = 1,644.72