Finding the Fourth Proportional to 1,522.89, 2,100.51 and 990.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,522.89 : 2,100.51 = 990.80 : x
2. Step 2: Convert to fraction form
   1,522.89/2,100.51 = 990.80/x
3. Step 3: Cross multiply
   1,522.89x = 2,100.51 × 990.80
4. Step 4: Simplify right side
   1,522.89x = 2,081,174.81
5. Step 5: Solve for x
   x = 2,081,174.81/1,522.89
6. Step 6: Final answer
   x = 1,366.60