Finding the Fourth Proportional to 1,502.56, 2,072.28 and 978.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,502.56 : 2,072.28 = 978.76 : x
2. Step 2: Convert to fraction form
   1,502.56/2,072.28 = 978.76/x
3. Step 3: Cross multiply
   1,502.56x = 2,072.28 × 978.76
4. Step 4: Simplify right side
   1,502.56x = 2,028,264.77
5. Step 5: Solve for x
   x = 2,028,264.77/1,502.56
6. Step 6: Final answer
   x = 1,349.87