Finding the Fourth Proportional to 1,608.30, 2,219.50 and 900.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,608.30 : 2,219.50 = 900.12 : x
2. Step 2: Convert to fraction form
   1,608.30/2,219.50 = 900.12/x
3. Step 3: Cross multiply
   1,608.30x = 2,219.50 × 900.12
4. Step 4: Simplify right side
   1,608.30x = 1,997,816.34
5. Step 5: Solve for x
   x = 1,997,816.34/1,608.30
6. Step 6: Final answer
   x = 1,242.19