Finding the Fourth Proportional to 2,384.31, 3,290.74 and 1,390.17

Step by Step Solution

1. Step 1: Write the proportion equation
   2,384.31 : 3,290.74 = 1,390.17 : x
2. Step 2: Convert to fraction form
   2,384.31/3,290.74 = 1,390.17/x
3. Step 3: Cross multiply
   2,384.31x = 3,290.74 × 1,390.17
4. Step 4: Simplify right side
   2,384.31x = 4,574,688.03
5. Step 5: Solve for x
   x = 4,574,688.03/2,384.31
6. Step 6: Final answer
   x = 1,918.66