Finding the Fourth Proportional to 1,667.78, 2,301.48 and 921.77

Step by Step Solution

1. Step 1: Write the proportion equation
   1,667.78 : 2,301.48 = 921.77 : x
2. Step 2: Convert to fraction form
   1,667.78/2,301.48 = 921.77/x
3. Step 3: Cross multiply
   1,667.78x = 2,301.48 × 921.77
4. Step 4: Simplify right side
   1,667.78x = 2,121,435.22
5. Step 5: Solve for x
   x = 2,121,435.22/1,667.78
6. Step 6: Final answer
   x = 1,272.01