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Finding the Fourth Proportional to 646.31, 969.62 and 213.47

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Solution

The fourth proportional to 646.31, 969.62 and 213.47 is: 320.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.31 : 969.62 = 213.47 : x
  2. Step 2: Convert to fraction form
    646.31/969.62 = 213.47/x
  3. Step 3: Cross multiply
    646.31x = 969.62 × 213.47
  4. Step 4: Simplify right side
    646.31x = 206,983.70
  5. Step 5: Solve for x
    x = 206,983.70/646.31
  6. Step 6: Final answer
    x = 320.25

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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.