Finding the Fourth Proportional to 1,538.16, 2,307.91 and 807.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,538.16 : 2,307.91 = 807.56 : x
2. Step 2: Convert to fraction form
   1,538.16/2,307.91 = 807.56/x
3. Step 3: Cross multiply
   1,538.16x = 2,307.91 × 807.56
4. Step 4: Simplify right side
   1,538.16x = 1,863,783.59
5. Step 5: Solve for x
   x = 1,863,783.59/1,538.16
6. Step 6: Final answer
   x = 1,211.70