Finding the Fourth Proportional to 1,561.49, 2,155.31 and 1,030.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.49 : 2,155.31 = 1,030.76 : x
2. Step 2: Convert to fraction form
   1,561.49/2,155.31 = 1,030.76/x
3. Step 3: Cross multiply
   1,561.49x = 2,155.31 × 1,030.76
4. Step 4: Simplify right side
   1,561.49x = 2,221,607.34
5. Step 5: Solve for x
   x = 2,221,607.34/1,561.49
6. Step 6: Final answer
   x = 1,422.75