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Finding the Fourth Proportional to 646.39, 969.57 and 213.55

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Solution

The fourth proportional to 646.39, 969.57 and 213.55 is: 320.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.39 : 969.57 = 213.55 : x
  2. Step 2: Convert to fraction form
    646.39/969.57 = 213.55/x
  3. Step 3: Cross multiply
    646.39x = 969.57 × 213.55
  4. Step 4: Simplify right side
    646.39x = 207,049.25
  5. Step 5: Solve for x
    x = 207,049.25/646.39
  6. Step 6: Final answer
    x = 320.32

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1.5x scale

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.