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Finding the Fourth Proportional to 646.76, 969.95 and 213.86

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Solution

The fourth proportional to 646.76, 969.95 and 213.86 is: 320.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.76 : 969.95 = 213.86 : x
  2. Step 2: Convert to fraction form
    646.76/969.95 = 213.86/x
  3. Step 3: Cross multiply
    646.76x = 969.95 × 213.86
  4. Step 4: Simplify right side
    646.76x = 207,429.19
  5. Step 5: Solve for x
    x = 207,429.19/646.76
  6. Step 6: Final answer
    x = 320.72

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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.