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Finding the Fourth Proportional to 286.64, 390.50 and 280.70

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Solution

The fourth proportional to 286.64, 390.50 and 280.70 is: 382.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.64 : 390.50 = 280.70 : x
  2. Step 2: Convert to fraction form
    286.64/390.50 = 280.70/x
  3. Step 3: Cross multiply
    286.64x = 390.50 × 280.70
  4. Step 4: Simplify right side
    286.64x = 109,613.35
  5. Step 5: Solve for x
    x = 109,613.35/286.64
  6. Step 6: Final answer
    x = 382.41

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.