Finding the Fourth Proportional to 1,157.89, 1,596.50 and 921.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,157.89 : 1,596.50 = 921.12 : x
2. Step 2: Convert to fraction form
   1,157.89/1,596.50 = 921.12/x
3. Step 3: Cross multiply
   1,157.89x = 1,596.50 × 921.12
4. Step 4: Simplify right side
   1,157.89x = 1,470,557.49
5. Step 5: Solve for x
   x = 1,470,557.49/1,157.89
6. Step 6: Final answer
   x = 1,270.03