Finding the Fourth Proportional to 1,427.90, 1,970.39 and 838.35

Step by Step Solution

1. Step 1: Write the proportion equation
   1,427.90 : 1,970.39 = 838.35 : x
2. Step 2: Convert to fraction form
   1,427.90/1,970.39 = 838.35/x
3. Step 3: Cross multiply
   1,427.90x = 1,970.39 × 838.35
4. Step 4: Simplify right side
   1,427.90x = 1,651,878.55
5. Step 5: Solve for x
   x = 1,651,878.55/1,427.90
6. Step 6: Final answer
   x = 1,156.86