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Finding the Fourth Proportional to 450.30, 676.80 and 390.90

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Solution

The fourth proportional to 450.30, 676.80 and 390.90 is: 587.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    450.30 : 676.80 = 390.90 : x
  2. Step 2: Convert to fraction form
    450.30/676.80 = 390.90/x
  3. Step 3: Cross multiply
    450.30x = 676.80 × 390.90
  4. Step 4: Simplify right side
    450.30x = 264,561.12
  5. Step 5: Solve for x
    x = 264,561.12/450.30
  6. Step 6: Final answer
    x = 587.52

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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.