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Finding the Fourth Proportional to 320.40, 480.55 and 89.23

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Solution

The fourth proportional to 320.40, 480.55 and 89.23 is: 133.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.40 : 480.55 = 89.23 : x
  2. Step 2: Convert to fraction form
    320.40/480.55 = 89.23/x
  3. Step 3: Cross multiply
    320.40x = 480.55 × 89.23
  4. Step 4: Simplify right side
    320.40x = 42,879.48
  5. Step 5: Solve for x
    x = 42,879.48/320.40
  6. Step 6: Final answer
    x = 133.83

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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.