Finding the Fourth Proportional to 2,547.12, 3,515.16 and 1,428

Step by Step Solution

1. Step 1: Write the proportion equation
   2,547.12 : 3,515.16 = 1,428 : x
2. Step 2: Convert to fraction form
   2,547.12/3,515.16 = 1,428/x
3. Step 3: Cross multiply
   2,547.12x = 3,515.16 × 1,428
4. Step 4: Simplify right side
   2,547.12x = 5,019,648.48
5. Step 5: Solve for x
   x = 5,019,648.48/2,547.12
6. Step 6: Final answer
   x = 1,970.72