Finding the Fourth Proportional to 1,530.40, 2,111.76 and 900.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,530.40 : 2,111.76 = 900.88 : x
2. Step 2: Convert to fraction form
   1,530.40/2,111.76 = 900.88/x
3. Step 3: Cross multiply
   1,530.40x = 2,111.76 × 900.88
4. Step 4: Simplify right side
   1,530.40x = 1,902,442.35
5. Step 5: Solve for x
   x = 1,902,442.35/1,530.40
6. Step 6: Final answer
   x = 1,243.10