Finding the Fourth Proportional to 1,380.48, 2,071.06 and 763.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.48 : 2,071.06 = 763.88 : x
2. Step 2: Convert to fraction form
   1,380.48/2,071.06 = 763.88/x
3. Step 3: Cross multiply
   1,380.48x = 2,071.06 × 763.88
4. Step 4: Simplify right side
   1,380.48x = 1,582,041.31
5. Step 5: Solve for x
   x = 1,582,041.31/1,380.48
6. Step 6: Final answer
   x = 1,146.01