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Finding the Fourth Proportional to 403.60, 606.30 and 387.20

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Solution

The fourth proportional to 403.60, 606.30 and 387.20 is: 581.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.60 : 606.30 = 387.20 : x
  2. Step 2: Convert to fraction form
    403.60/606.30 = 387.20/x
  3. Step 3: Cross multiply
    403.60x = 606.30 × 387.20
  4. Step 4: Simplify right side
    403.60x = 234,759.36
  5. Step 5: Solve for x
    x = 234,759.36/403.60
  6. Step 6: Final answer
    x = 581.66

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.