Finding the Fourth Proportional to 1,389.56, 1,918.77 and 893.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.56 : 1,918.77 = 893.30 : x
2. Step 2: Convert to fraction form
   1,389.56/1,918.77 = 893.30/x
3. Step 3: Cross multiply
   1,389.56x = 1,918.77 × 893.30
4. Step 4: Simplify right side
   1,389.56x = 1,714,037.24
5. Step 5: Solve for x
   x = 1,714,037.24/1,389.56
6. Step 6: Final answer
   x = 1,233.51