Finding the Fourth Proportional to 1,667.40, 2,310.74 and 1,643.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,667.40 : 2,310.74 = 1,643.91 : x
2. Step 2: Convert to fraction form
   1,667.40/2,310.74 = 1,643.91/x
3. Step 3: Cross multiply
   1,667.40x = 2,310.74 × 1,643.91
4. Step 4: Simplify right side
   1,667.40x = 3,798,648.59
5. Step 5: Solve for x
   x = 3,798,648.59/1,667.40
6. Step 6: Final answer
   x = 2,278.19