Finding the Fourth Proportional to 2,139.82, 3,207.30 and 970.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.82 : 3,207.30 = 970.72 : x
2. Step 2: Convert to fraction form
   2,139.82/3,207.30 = 970.72/x
3. Step 3: Cross multiply
   2,139.82x = 3,207.30 × 970.72
4. Step 4: Simplify right side
   2,139.82x = 3,113,390.26
5. Step 5: Solve for x
   x = 3,113,390.26/2,139.82
6. Step 6: Final answer
   x = 1,454.98