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Finding the Fourth Proportional to 856.39, 1,284.60 and 343.39

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Solution

The fourth proportional to 856.39, 1,284.60 and 343.39 is: 515.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.39 : 1,284.60 = 343.39 : x
  2. Step 2: Convert to fraction form
    856.39/1,284.60 = 343.39/x
  3. Step 3: Cross multiply
    856.39x = 1,284.60 × 343.39
  4. Step 4: Simplify right side
    856.39x = 441,118.79
  5. Step 5: Solve for x
    x = 441,118.79/856.39
  6. Step 6: Final answer
    x = 515.09

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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.