Finding the Fourth Proportional to 1,422.56, 1,970.73 and 1,388.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,422.56 : 1,970.73 = 1,388.54 : x
2. Step 2: Convert to fraction form
   1,422.56/1,970.73 = 1,388.54/x
3. Step 3: Cross multiply
   1,422.56x = 1,970.73 × 1,388.54
4. Step 4: Simplify right side
   1,422.56x = 2,736,427.58
5. Step 5: Solve for x
   x = 2,736,427.58/1,422.56
6. Step 6: Final answer
   x = 1,923.60