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Finding the Fourth Proportional to 487.05, 672.81 and 388.68

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Solution

The fourth proportional to 487.05, 672.81 and 388.68 is: 536.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.05 : 672.81 = 388.68 : x
  2. Step 2: Convert to fraction form
    487.05/672.81 = 388.68/x
  3. Step 3: Cross multiply
    487.05x = 672.81 × 388.68
  4. Step 4: Simplify right side
    487.05x = 261,507.79
  5. Step 5: Solve for x
    x = 261,507.79/487.05
  6. Step 6: Final answer
    x = 536.92

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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.