Finding the Fourth Proportional to 2,547.86, 3,515.81 and 1,428.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,547.86 : 3,515.81 = 1,428.84 : x
2. Step 2: Convert to fraction form
   2,547.86/3,515.81 = 1,428.84/x
3. Step 3: Cross multiply
   2,547.86x = 3,515.81 × 1,428.84
4. Step 4: Simplify right side
   2,547.86x = 5,023,522.82
5. Step 5: Solve for x
   x = 5,023,522.82/2,547.86
6. Step 6: Final answer
   x = 1,971.67