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Finding the Fourth Proportional to 420.01, 579.72 and 280.39

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Solution

The fourth proportional to 420.01, 579.72 and 280.39 is: 387.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.01 : 579.72 = 280.39 : x
  2. Step 2: Convert to fraction form
    420.01/579.72 = 280.39/x
  3. Step 3: Cross multiply
    420.01x = 579.72 × 280.39
  4. Step 4: Simplify right side
    420.01x = 162,547.69
  5. Step 5: Solve for x
    x = 162,547.69/420.01
  6. Step 6: Final answer
    x = 387.01

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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.