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Finding the Fourth Proportional to 287.10, 431.55 and 281.70

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Solution

The fourth proportional to 287.10, 431.55 and 281.70 is: 423.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.10 : 431.55 = 281.70 : x
  2. Step 2: Convert to fraction form
    287.10/431.55 = 281.70/x
  3. Step 3: Cross multiply
    287.10x = 431.55 × 281.70
  4. Step 4: Simplify right side
    287.10x = 121,567.64
  5. Step 5: Solve for x
    x = 121,567.64/287.10
  6. Step 6: Final answer
    x = 423.43

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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.