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Finding the Fourth Proportional to 630.30, 869.26 and 420.47

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Solution

The fourth proportional to 630.30, 869.26 and 420.47 is: 579.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.30 : 869.26 = 420.47 : x
  2. Step 2: Convert to fraction form
    630.30/869.26 = 420.47/x
  3. Step 3: Cross multiply
    630.30x = 869.26 × 420.47
  4. Step 4: Simplify right side
    630.30x = 365,497.75
  5. Step 5: Solve for x
    x = 365,497.75/630.30
  6. Step 6: Final answer
    x = 579.88

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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.