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Finding the Fourth Proportional to 320.40, 480.50 and 155.78

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Solution

The fourth proportional to 320.40, 480.50 and 155.78 is: 233.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.40 : 480.50 = 155.78 : x
  2. Step 2: Convert to fraction form
    320.40/480.50 = 155.78/x
  3. Step 3: Cross multiply
    320.40x = 480.50 × 155.78
  4. Step 4: Simplify right side
    320.40x = 74,849.11
  5. Step 5: Solve for x
    x = 74,849.11/320.40
  6. Step 6: Final answer
    x = 233.61

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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.