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Finding the Fourth Proportional to 721.91, 996.69 and 500.78

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Solution

The fourth proportional to 721.91, 996.69 and 500.78 is: 691.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.91 : 996.69 = 500.78 : x
  2. Step 2: Convert to fraction form
    721.91/996.69 = 500.78/x
  3. Step 3: Cross multiply
    721.91x = 996.69 × 500.78
  4. Step 4: Simplify right side
    721.91x = 499,117.43
  5. Step 5: Solve for x
    x = 499,117.43/721.91
  6. Step 6: Final answer
    x = 691.39

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Double scale
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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.