Finding the Fourth Proportional to 2,611.72, 3,918.72 and 1,378.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,611.72 : 3,918.72 = 1,378.84 : x
2. Step 2: Convert to fraction form
   2,611.72/3,918.72 = 1,378.84/x
3. Step 3: Cross multiply
   2,611.72x = 3,918.72 × 1,378.84
4. Step 4: Simplify right side
   2,611.72x = 5,403,287.88
5. Step 5: Solve for x
   x = 5,403,287.88/2,611.72
6. Step 6: Final answer
   x = 2,068.86