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Finding the Fourth Proportional to 480.45, 720.78 and 155.81

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Solution

The fourth proportional to 480.45, 720.78 and 155.81 is: 233.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    480.45 : 720.78 = 155.81 : x
  2. Step 2: Convert to fraction form
    480.45/720.78 = 155.81/x
  3. Step 3: Cross multiply
    480.45x = 720.78 × 155.81
  4. Step 4: Simplify right side
    480.45x = 112,306.83
  5. Step 5: Solve for x
    x = 112,306.83/480.45
  6. Step 6: Final answer
    x = 233.75

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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.