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Finding the Fourth Proportional to 387.65, 579.15 and 306.55

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Solution

The fourth proportional to 387.65, 579.15 and 306.55 is: 457.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.65 : 579.15 = 306.55 : x
  2. Step 2: Convert to fraction form
    387.65/579.15 = 306.55/x
  3. Step 3: Cross multiply
    387.65x = 579.15 × 306.55
  4. Step 4: Simplify right side
    387.65x = 177,539.16
  5. Step 5: Solve for x
    x = 177,539.16/387.65
  6. Step 6: Final answer
    x = 457.99

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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.