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Finding the Fourth Proportional to 287.15, 431.21 and 272.54

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Solution

The fourth proportional to 287.15, 431.21 and 272.54 is: 409.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.15 : 431.21 = 272.54 : x
  2. Step 2: Convert to fraction form
    287.15/431.21 = 272.54/x
  3. Step 3: Cross multiply
    287.15x = 431.21 × 272.54
  4. Step 4: Simplify right side
    287.15x = 117,521.97
  5. Step 5: Solve for x
    x = 117,521.97/287.15
  6. Step 6: Final answer
    x = 409.27

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.