Finding the Fourth Proportional to 1,801.72, 2,486.76 and 1,138.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,801.72 : 2,486.76 = 1,138.15 : x
2. Step 2: Convert to fraction form
   1,801.72/2,486.76 = 1,138.15/x
3. Step 3: Cross multiply
   1,801.72x = 2,486.76 × 1,138.15
4. Step 4: Simplify right side
   1,801.72x = 2,830,305.89
5. Step 5: Solve for x
   x = 2,830,305.89/1,801.72
6. Step 6: Final answer
   x = 1,570.89