Finding the Fourth Proportional to 1,401.90, 2,101.05 and 1,254.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,401.90 : 2,101.05 = 1,254.78 : x
2. Step 2: Convert to fraction form
   1,401.90/2,101.05 = 1,254.78/x
3. Step 3: Cross multiply
   1,401.90x = 2,101.05 × 1,254.78
4. Step 4: Simplify right side
   1,401.90x = 2,636,355.52
5. Step 5: Solve for x
   x = 2,636,355.52/1,401.90
6. Step 6: Final answer
   x = 1,880.56