Finding the Fourth Proportional to 1,403.40, 1,937.52 and 906.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,403.40 : 1,937.52 = 906.78 : x
2. Step 2: Convert to fraction form
   1,403.40/1,937.52 = 906.78/x
3. Step 3: Cross multiply
   1,403.40x = 1,937.52 × 906.78
4. Step 4: Simplify right side
   1,403.40x = 1,756,904.39
5. Step 5: Solve for x
   x = 1,756,904.39/1,403.40
6. Step 6: Final answer
   x = 1,251.89