Finding the Fourth Proportional to 1,345.80, 1,855.86 and 821.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,345.80 : 1,855.86 = 821.52 : x
2. Step 2: Convert to fraction form
   1,345.80/1,855.86 = 821.52/x
3. Step 3: Cross multiply
   1,345.80x = 1,855.86 × 821.52
4. Step 4: Simplify right side
   1,345.80x = 1,524,626.11
5. Step 5: Solve for x
   x = 1,524,626.11/1,345.80
6. Step 6: Final answer
   x = 1,132.88