Finding the Fourth Proportional to 1,439.50, 2,155.60 and 890.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,439.50 : 2,155.60 = 890.02 : x
2. Step 2: Convert to fraction form
   1,439.50/2,155.60 = 890.02/x
3. Step 3: Cross multiply
   1,439.50x = 2,155.60 × 890.02
4. Step 4: Simplify right side
   1,439.50x = 1,918,516.33
5. Step 5: Solve for x
   x = 1,918,516.33/1,439.50
6. Step 6: Final answer
   x = 1,332.77