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Finding the Fourth Proportional to 284.40, 391.64 and 278.36

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Solution

The fourth proportional to 284.40, 391.64 and 278.36 is: 383.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.40 : 391.64 = 278.36 : x
  2. Step 2: Convert to fraction form
    284.40/391.64 = 278.36/x
  3. Step 3: Cross multiply
    284.40x = 391.64 × 278.36
  4. Step 4: Simplify right side
    284.40x = 109,016.91
  5. Step 5: Solve for x
    x = 109,016.91/284.40
  6. Step 6: Final answer
    x = 383.32

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.