Finding the Fourth Proportional to 1,561.53, 2,339.55 and 1,316.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.53 : 2,339.55 = 1,316.31 : x
2. Step 2: Convert to fraction form
   1,561.53/2,339.55 = 1,316.31/x
3. Step 3: Cross multiply
   1,561.53x = 2,339.55 × 1,316.31
4. Step 4: Simplify right side
   1,561.53x = 3,079,573.06
5. Step 5: Solve for x
   x = 3,079,573.06/1,561.53
6. Step 6: Final answer
   x = 1,972.15