Finding the Fourth Proportional to 1,686.17, 2,530.34 and 820.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,686.17 : 2,530.34 = 820.01 : x
2. Step 2: Convert to fraction form
   1,686.17/2,530.34 = 820.01/x
3. Step 3: Cross multiply
   1,686.17x = 2,530.34 × 820.01
4. Step 4: Simplify right side
   1,686.17x = 2,074,904.10
5. Step 5: Solve for x
   x = 2,074,904.10/1,686.17
6. Step 6: Final answer
   x = 1,230.54