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Finding the Fourth Proportional to 645.70, 890.84 and 412.96

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Solution

The fourth proportional to 645.70, 890.84 and 412.96 is: 569.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.70 : 890.84 = 412.96 : x
  2. Step 2: Convert to fraction form
    645.70/890.84 = 412.96/x
  3. Step 3: Cross multiply
    645.70x = 890.84 × 412.96
  4. Step 4: Simplify right side
    645.70x = 367,881.29
  5. Step 5: Solve for x
    x = 367,881.29/645.70
  6. Step 6: Final answer
    x = 569.74

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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.