Finding the Fourth Proportional to 1,561.76, 2,154.71 and 1,030.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.76 : 2,154.71 = 1,030.90 : x
2. Step 2: Convert to fraction form
   1,561.76/2,154.71 = 1,030.90/x
3. Step 3: Cross multiply
   1,561.76x = 2,154.71 × 1,030.90
4. Step 4: Simplify right side
   1,561.76x = 2,221,290.54
5. Step 5: Solve for x
   x = 2,221,290.54/1,561.76
6. Step 6: Final answer
   x = 1,422.30