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Finding the Fourth Proportional to 387.20, 534.38 and 219.18

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Solution

The fourth proportional to 387.20, 534.38 and 219.18 is: 302.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.20 : 534.38 = 219.18 : x
  2. Step 2: Convert to fraction form
    387.20/534.38 = 219.18/x
  3. Step 3: Cross multiply
    387.20x = 534.38 × 219.18
  4. Step 4: Simplify right side
    387.20x = 117,125.41
  5. Step 5: Solve for x
    x = 117,125.41/387.20
  6. Step 6: Final answer
    x = 302.49

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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.