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Finding the Fourth Proportional to 856.35, 1,284.62 and 279.09

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Solution

The fourth proportional to 856.35, 1,284.62 and 279.09 is: 418.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.35 : 1,284.62 = 279.09 : x
  2. Step 2: Convert to fraction form
    856.35/1,284.62 = 279.09/x
  3. Step 3: Cross multiply
    856.35x = 1,284.62 × 279.09
  4. Step 4: Simplify right side
    856.35x = 358,523.20
  5. Step 5: Solve for x
    x = 358,523.20/856.35
  6. Step 6: Final answer
    x = 418.66

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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.