Finding the Fourth Proportional to 1,011.72, 1,521.27 and 931.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,011.72 : 1,521.27 = 931.53 : x
2. Step 2: Convert to fraction form
   1,011.72/1,521.27 = 931.53/x
3. Step 3: Cross multiply
   1,011.72x = 1,521.27 × 931.53
4. Step 4: Simplify right side
   1,011.72x = 1,417,108.64
5. Step 5: Solve for x
   x = 1,417,108.64/1,011.72
6. Step 6: Final answer
   x = 1,400.69