Finding the Fourth Proportional to 1,555.31, 2,331.54 and 1,420.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,555.31 : 2,331.54 = 1,420.04 : x
2. Step 2: Convert to fraction form
   1,555.31/2,331.54 = 1,420.04/x
3. Step 3: Cross multiply
   1,555.31x = 2,331.54 × 1,420.04
4. Step 4: Simplify right side
   1,555.31x = 3,310,885.89
5. Step 5: Solve for x
   x = 3,310,885.89/1,555.31
6. Step 6: Final answer
   x = 2,128.76