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Finding the Fourth Proportional to 646.39, 969.68 and 213.45

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Solution

The fourth proportional to 646.39, 969.68 and 213.45 is: 320.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.39 : 969.68 = 213.45 : x
  2. Step 2: Convert to fraction form
    646.39/969.68 = 213.45/x
  3. Step 3: Cross multiply
    646.39x = 969.68 × 213.45
  4. Step 4: Simplify right side
    646.39x = 206,978.20
  5. Step 5: Solve for x
    x = 206,978.20/646.39
  6. Step 6: Final answer
    x = 320.21

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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.