Finding the Fourth Proportional to 2,570.72, 3,547.58 and 1,391.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,570.72 : 3,547.58 = 1,391.78 : x
2. Step 2: Convert to fraction form
   2,570.72/3,547.58 = 1,391.78/x
3. Step 3: Cross multiply
   2,570.72x = 3,547.58 × 1,391.78
4. Step 4: Simplify right side
   2,570.72x = 4,937,450.89
5. Step 5: Solve for x
   x = 4,937,450.89/2,570.72
6. Step 6: Final answer
   x = 1,920.65