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Finding the Fourth Proportional to 487.21, 672.15 and 288.07

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Solution

The fourth proportional to 487.21, 672.15 and 288.07 is: 397.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.21 : 672.15 = 288.07 : x
  2. Step 2: Convert to fraction form
    487.21/672.15 = 288.07/x
  3. Step 3: Cross multiply
    487.21x = 672.15 × 288.07
  4. Step 4: Simplify right side
    487.21x = 193,624.57
  5. Step 5: Solve for x
    x = 193,624.57/487.21
  6. Step 6: Final answer
    x = 397.42

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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.