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Finding the Fourth Proportional to 449.70, 674.55 and 390.30

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Solution

The fourth proportional to 449.70, 674.55 and 390.30 is: 585.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    449.70 : 674.55 = 390.30 : x
  2. Step 2: Convert to fraction form
    449.70/674.55 = 390.30/x
  3. Step 3: Cross multiply
    449.70x = 674.55 × 390.30
  4. Step 4: Simplify right side
    449.70x = 263,276.87
  5. Step 5: Solve for x
    x = 263,276.87/449.70
  6. Step 6: Final answer
    x = 585.45

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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.