Finding the Fourth Proportional to 1,430.76, 1,974.36 and 1,388.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,430.76 : 1,974.36 = 1,388.82 : x
2. Step 2: Convert to fraction form
   1,430.76/1,974.36 = 1,388.82/x
3. Step 3: Cross multiply
   1,430.76x = 1,974.36 × 1,388.82
4. Step 4: Simplify right side
   1,430.76x = 2,742,030.66
5. Step 5: Solve for x
   x = 2,742,030.66/1,430.76
6. Step 6: Final answer
   x = 1,916.49