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Finding the Fourth Proportional to 287.42, 399.39 and 284.45

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Solution

The fourth proportional to 287.42, 399.39 and 284.45 is: 395.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.42 : 399.39 = 284.45 : x
  2. Step 2: Convert to fraction form
    287.42/399.39 = 284.45/x
  3. Step 3: Cross multiply
    287.42x = 399.39 × 284.45
  4. Step 4: Simplify right side
    287.42x = 113,604.49
  5. Step 5: Solve for x
    x = 113,604.49/287.42
  6. Step 6: Final answer
    x = 395.26

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.