Finding the Fourth Proportional to 2,547.38, 3,515.35 and 1,428.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,547.38 : 3,515.35 = 1,428.31 : x
2. Step 2: Convert to fraction form
   2,547.38/3,515.35 = 1,428.31/x
3. Step 3: Cross multiply
   2,547.38x = 3,515.35 × 1,428.31
4. Step 4: Simplify right side
   2,547.38x = 5,021,009.56
5. Step 5: Solve for x
   x = 5,021,009.56/2,547.38
6. Step 6: Final answer
   x = 1,971.05