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Finding the Fourth Proportional to 649.80, 974.70 and 431.10

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Solution

The fourth proportional to 649.80, 974.70 and 431.10 is: 646.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.80 : 974.70 = 431.10 : x
  2. Step 2: Convert to fraction form
    649.80/974.70 = 431.10/x
  3. Step 3: Cross multiply
    649.80x = 974.70 × 431.10
  4. Step 4: Simplify right side
    649.80x = 420,193.17
  5. Step 5: Solve for x
    x = 420,193.17/649.80
  6. Step 6: Final answer
    x = 646.65

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Double scale
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Similar ratio
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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.