Finding the Fourth Proportional to 2,646.71, 3,970.02 and 915.29

Step by Step Solution

1. Step 1: Write the proportion equation
   2,646.71 : 3,970.02 = 915.29 : x
2. Step 2: Convert to fraction form
   2,646.71/3,970.02 = 915.29/x
3. Step 3: Cross multiply
   2,646.71x = 3,970.02 × 915.29
4. Step 4: Simplify right side
   2,646.71x = 3,633,719.61
5. Step 5: Solve for x
   x = 3,633,719.61/2,646.71
6. Step 6: Final answer
   x = 1,372.92