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Finding the Fourth Proportional to 639.39, 880.29 and 442.56

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Solution

The fourth proportional to 639.39, 880.29 and 442.56 is: 609.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.39 : 880.29 = 442.56 : x
  2. Step 2: Convert to fraction form
    639.39/880.29 = 442.56/x
  3. Step 3: Cross multiply
    639.39x = 880.29 × 442.56
  4. Step 4: Simplify right side
    639.39x = 389,581.14
  5. Step 5: Solve for x
    x = 389,581.14/639.39
  6. Step 6: Final answer
    x = 609.30

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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.