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Finding the Fourth Proportional to 646.68, 969.88 and 213.84

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Solution

The fourth proportional to 646.68, 969.88 and 213.84 is: 320.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.68 : 969.88 = 213.84 : x
  2. Step 2: Convert to fraction form
    646.68/969.88 = 213.84/x
  3. Step 3: Cross multiply
    646.68x = 969.88 × 213.84
  4. Step 4: Simplify right side
    646.68x = 207,399.14
  5. Step 5: Solve for x
    x = 207,399.14/646.68
  6. Step 6: Final answer
    x = 320.71

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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.