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Finding the Fourth Proportional to 320.79, 480.78 and 280.02

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Solution

The fourth proportional to 320.79, 480.78 and 280.02 is: 419.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.79 : 480.78 = 280.02 : x
  2. Step 2: Convert to fraction form
    320.79/480.78 = 280.02/x
  3. Step 3: Cross multiply
    320.79x = 480.78 × 280.02
  4. Step 4: Simplify right side
    320.79x = 134,628.02
  5. Step 5: Solve for x
    x = 134,628.02/320.79
  6. Step 6: Final answer
    x = 419.68

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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.