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Finding the Fourth Proportional to 287.72, 429.40 and 255.32

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Solution

The fourth proportional to 287.72, 429.40 and 255.32 is: 381.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.72 : 429.40 = 255.32 : x
  2. Step 2: Convert to fraction form
    287.72/429.40 = 255.32/x
  3. Step 3: Cross multiply
    287.72x = 429.40 × 255.32
  4. Step 4: Simplify right side
    287.72x = 109,634.41
  5. Step 5: Solve for x
    x = 109,634.41/287.72
  6. Step 6: Final answer
    x = 381.05

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.