Finding the Fourth Proportional to 1,445.21, 2,152.89 and 1,355.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,445.21 : 2,152.89 = 1,355.57 : x
2. Step 2: Convert to fraction form
   1,445.21/2,152.89 = 1,355.57/x
3. Step 3: Cross multiply
   1,445.21x = 2,152.89 × 1,355.57
4. Step 4: Simplify right side
   1,445.21x = 2,918,382.33
5. Step 5: Solve for x
   x = 2,918,382.33/1,445.21
6. Step 6: Final answer
   x = 2,019.36