Finding the Fourth Proportional to 1,345.25, 1,856.65 and 821.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,345.25 : 1,856.65 = 821.59 : x
2. Step 2: Convert to fraction form
   1,345.25/1,856.65 = 821.59/x
3. Step 3: Cross multiply
   1,345.25x = 1,856.65 × 821.59
4. Step 4: Simplify right side
   1,345.25x = 1,525,405.07
5. Step 5: Solve for x
   x = 1,525,405.07/1,345.25
6. Step 6: Final answer
   x = 1,133.92