Finding the Fourth Proportional to 2,084.17, 2,864.12 and 1,987.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,084.17 : 2,864.12 = 1,987.80 : x
2. Step 2: Convert to fraction form
   2,084.17/2,864.12 = 1,987.80/x
3. Step 3: Cross multiply
   2,084.17x = 2,864.12 × 1,987.80
4. Step 4: Simplify right side
   2,084.17x = 5,693,297.74
5. Step 5: Solve for x
   x = 5,693,297.74/2,084.17
6. Step 6: Final answer
   x = 2,731.69