Finding the Fourth Proportional to 1,561.31, 2,152.13 and 1,229.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.31 : 2,152.13 = 1,229.30 : x
2. Step 2: Convert to fraction form
   1,561.31/2,152.13 = 1,229.30/x
3. Step 3: Cross multiply
   1,561.31x = 2,152.13 × 1,229.30
4. Step 4: Simplify right side
   1,561.31x = 2,645,596.50
5. Step 5: Solve for x
   x = 2,645,596.50/1,561.31
6. Step 6: Final answer
   x = 1,694.48