Finding the Fourth Proportional to 1,781.34, 2,459.61 and 1,389.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,781.34 : 2,459.61 = 1,389.30 : x
2. Step 2: Convert to fraction form
   1,781.34/2,459.61 = 1,389.30/x
3. Step 3: Cross multiply
   1,781.34x = 2,459.61 × 1,389.30
4. Step 4: Simplify right side
   1,781.34x = 3,417,136.17
5. Step 5: Solve for x
   x = 3,417,136.17/1,781.34
6. Step 6: Final answer
   x = 1,918.30