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Finding the Fourth Proportional to 856.71, 1,284.28 and 417.71

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Solution

The fourth proportional to 856.71, 1,284.28 and 417.71 is: 626.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.71 : 1,284.28 = 417.71 : x
  2. Step 2: Convert to fraction form
    856.71/1,284.28 = 417.71/x
  3. Step 3: Cross multiply
    856.71x = 1,284.28 × 417.71
  4. Step 4: Simplify right side
    856.71x = 536,458.77
  5. Step 5: Solve for x
    x = 536,458.77/856.71
  6. Step 6: Final answer
    x = 626.18

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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.