Finding the Fourth Proportional to 2,647.32, 3,970.94 and 915.96

Step by Step Solution

1. Step 1: Write the proportion equation
   2,647.32 : 3,970.94 = 915.96 : x
2. Step 2: Convert to fraction form
   2,647.32/3,970.94 = 915.96/x
3. Step 3: Cross multiply
   2,647.32x = 3,970.94 × 915.96
4. Step 4: Simplify right side
   2,647.32x = 3,637,222.20
5. Step 5: Solve for x
   x = 3,637,222.20/2,647.32
6. Step 6: Final answer
   x = 1,373.93