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Finding the Fourth Proportional to 419.95, 579.73 and 280.30

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Solution

The fourth proportional to 419.95, 579.73 and 280.30 is: 386.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.95 : 579.73 = 280.30 : x
  2. Step 2: Convert to fraction form
    419.95/579.73 = 280.30/x
  3. Step 3: Cross multiply
    419.95x = 579.73 × 280.30
  4. Step 4: Simplify right side
    419.95x = 162,498.32
  5. Step 5: Solve for x
    x = 162,498.32/419.95
  6. Step 6: Final answer
    x = 386.95

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.