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Finding the Fourth Proportional to 606.40, 909.60 and 420.10

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Solution

The fourth proportional to 606.40, 909.60 and 420.10 is: 630.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    606.40 : 909.60 = 420.10 : x
  2. Step 2: Convert to fraction form
    606.40/909.60 = 420.10/x
  3. Step 3: Cross multiply
    606.40x = 909.60 × 420.10
  4. Step 4: Simplify right side
    606.40x = 382,122.96
  5. Step 5: Solve for x
    x = 382,122.96/606.40
  6. Step 6: Final answer
    x = 630.15

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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.