Finding the Fourth Proportional to 1,405.72, 1,938.80 and 908.41

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.72 : 1,938.80 = 908.41 : x
2. Step 2: Convert to fraction form
   1,405.72/1,938.80 = 908.41/x
3. Step 3: Cross multiply
   1,405.72x = 1,938.80 × 908.41
4. Step 4: Simplify right side
   1,405.72x = 1,761,220.77
5. Step 5: Solve for x
   x = 1,761,220.77/1,405.72
6. Step 6: Final answer
   x = 1,252.90