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Finding the Fourth Proportional to 519.28, 715.32 and 420.76

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Solution

The fourth proportional to 519.28, 715.32 and 420.76 is: 579.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.28 : 715.32 = 420.76 : x
  2. Step 2: Convert to fraction form
    519.28/715.32 = 420.76/x
  3. Step 3: Cross multiply
    519.28x = 715.32 × 420.76
  4. Step 4: Simplify right side
    519.28x = 300,978.04
  5. Step 5: Solve for x
    x = 300,978.04/519.28
  6. Step 6: Final answer
    x = 579.61

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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.