Finding the Fourth Proportional to 1,667.59, 2,301.28 and 921.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,667.59 : 2,301.28 = 921.55 : x
2. Step 2: Convert to fraction form
   1,667.59/2,301.28 = 921.55/x
3. Step 3: Cross multiply
   1,667.59x = 2,301.28 × 921.55
4. Step 4: Simplify right side
   1,667.59x = 2,120,728.47
5. Step 5: Solve for x
   x = 2,120,728.47/1,667.59
6. Step 6: Final answer
   x = 1,271.74