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Finding the Fourth Proportional to 645.71, 891.28 and 412.83

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Solution

The fourth proportional to 645.71, 891.28 and 412.83 is: 569.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.71 : 891.28 = 412.83 : x
  2. Step 2: Convert to fraction form
    645.71/891.28 = 412.83/x
  3. Step 3: Cross multiply
    645.71x = 891.28 × 412.83
  4. Step 4: Simplify right side
    645.71x = 367,946.09
  5. Step 5: Solve for x
    x = 367,946.09/645.71
  6. Step 6: Final answer
    x = 569.84

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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.