Finding the Fourth Proportional to 1,061.85, 1,591.23 and 989.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.85 : 1,591.23 = 989.58 : x
2. Step 2: Convert to fraction form
   1,061.85/1,591.23 = 989.58/x
3. Step 3: Cross multiply
   1,061.85x = 1,591.23 × 989.58
4. Step 4: Simplify right side
   1,061.85x = 1,574,649.38
5. Step 5: Solve for x
   x = 1,574,649.38/1,061.85
6. Step 6: Final answer
   x = 1,482.93