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Finding the Fourth Proportional to 442.18, 660.30 and 387.50

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Solution

The fourth proportional to 442.18, 660.30 and 387.50 is: 578.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    442.18 : 660.30 = 387.50 : x
  2. Step 2: Convert to fraction form
    442.18/660.30 = 387.50/x
  3. Step 3: Cross multiply
    442.18x = 660.30 × 387.50
  4. Step 4: Simplify right side
    442.18x = 255,866.25
  5. Step 5: Solve for x
    x = 255,866.25/442.18
  6. Step 6: Final answer
    x = 578.65

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.