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Finding the Fourth Proportional to 680.39, 939.39 and 471.21

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Solution

The fourth proportional to 680.39, 939.39 and 471.21 is: 650.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.39 : 939.39 = 471.21 : x
  2. Step 2: Convert to fraction form
    680.39/939.39 = 471.21/x
  3. Step 3: Cross multiply
    680.39x = 939.39 × 471.21
  4. Step 4: Simplify right side
    680.39x = 442,650.87
  5. Step 5: Solve for x
    x = 442,650.87/680.39
  6. Step 6: Final answer
    x = 650.58

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.