Finding the Fourth Proportional to 1,542.32, 2,128.61 and 912.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,542.32 : 2,128.61 = 912.80 : x
2. Step 2: Convert to fraction form
   1,542.32/2,128.61 = 912.80/x
3. Step 3: Cross multiply
   1,542.32x = 2,128.61 × 912.80
4. Step 4: Simplify right side
   1,542.32x = 1,942,980.00
5. Step 5: Solve for x
   x = 1,942,980.00/1,542.32
6. Step 6: Final answer
   x = 1,259.78