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Finding the Fourth Proportional to 561.38, 775.31 and 387.23

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Solution

The fourth proportional to 561.38, 775.31 and 387.23 is: 534.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.38 : 775.31 = 387.23 : x
  2. Step 2: Convert to fraction form
    561.38/775.31 = 387.23/x
  3. Step 3: Cross multiply
    561.38x = 775.31 × 387.23
  4. Step 4: Simplify right side
    561.38x = 300,217.48
  5. Step 5: Solve for x
    x = 300,217.48/561.38
  6. Step 6: Final answer
    x = 534.79

Related Problems

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Half scale
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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.