Finding the Fourth Proportional to 1,645.40, 2,461.59 and 915.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,645.40 : 2,461.59 = 915.45 : x
2. Step 2: Convert to fraction form
   1,645.40/2,461.59 = 915.45/x
3. Step 3: Cross multiply
   1,645.40x = 2,461.59 × 915.45
4. Step 4: Simplify right side
   1,645.40x = 2,253,462.57
5. Step 5: Solve for x
   x = 2,253,462.57/1,645.40
6. Step 6: Final answer
   x = 1,369.56