Finding the Fourth Proportional to 1,451.40, 2,002.78 and 891.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,451.40 : 2,002.78 = 891.89 : x
2. Step 2: Convert to fraction form
   1,451.40/2,002.78 = 891.89/x
3. Step 3: Cross multiply
   1,451.40x = 2,002.78 × 891.89
4. Step 4: Simplify right side
   1,451.40x = 1,786,259.45
5. Step 5: Solve for x
   x = 1,786,259.45/1,451.40
6. Step 6: Final answer
   x = 1,230.71