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Finding the Fourth Proportional to 646.50, 969.82 and 213.64

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Solution

The fourth proportional to 646.50, 969.82 and 213.64 is: 320.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.50 : 969.82 = 213.64 : x
  2. Step 2: Convert to fraction form
    646.50/969.82 = 213.64/x
  3. Step 3: Cross multiply
    646.50x = 969.82 × 213.64
  4. Step 4: Simplify right side
    646.50x = 207,192.34
  5. Step 5: Solve for x
    x = 207,192.34/646.50
  6. Step 6: Final answer
    x = 320.48

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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.