Finding the Fourth Proportional to 1,528.22, 2,108.77 and 856.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,528.22 : 2,108.77 = 856.05 : x
2. Step 2: Convert to fraction form
   1,528.22/2,108.77 = 856.05/x
3. Step 3: Cross multiply
   1,528.22x = 2,108.77 × 856.05
4. Step 4: Simplify right side
   1,528.22x = 1,805,212.56
5. Step 5: Solve for x
   x = 1,805,212.56/1,528.22
6. Step 6: Final answer
   x = 1,181.25