Finding the Fourth Proportional to 1,378.16, 2,062.43 and 1,128.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,378.16 : 2,062.43 = 1,128.48 : x
2. Step 2: Convert to fraction form
   1,378.16/2,062.43 = 1,128.48/x
3. Step 3: Cross multiply
   1,378.16x = 2,062.43 × 1,128.48
4. Step 4: Simplify right side
   1,378.16x = 2,327,411.01
5. Step 5: Solve for x
   x = 2,327,411.01/1,378.16
6. Step 6: Final answer
   x = 1,688.78