Finding the Fourth Proportional to 1,355.81, 1,870.29 and 913.95

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.81 : 1,870.29 = 913.95 : x
2. Step 2: Convert to fraction form
   1,355.81/1,870.29 = 913.95/x
3. Step 3: Cross multiply
   1,355.81x = 1,870.29 × 913.95
4. Step 4: Simplify right side
   1,355.81x = 1,709,351.55
5. Step 5: Solve for x
   x = 1,709,351.55/1,355.81
6. Step 6: Final answer
   x = 1,260.77