Finding the Fourth Proportional to 2,128.06, 2,935.29 and 1,288.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.06 : 2,935.29 = 1,288.18 : x
2. Step 2: Convert to fraction form
   2,128.06/2,935.29 = 1,288.18/x
3. Step 3: Cross multiply
   2,128.06x = 2,935.29 × 1,288.18
4. Step 4: Simplify right side
   2,128.06x = 3,781,181.87
5. Step 5: Solve for x
   x = 3,781,181.87/2,128.06
6. Step 6: Final answer
   x = 1,776.82