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Finding the Fourth Proportional to 480.78, 717.89 and 398.57

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Solution

The fourth proportional to 480.78, 717.89 and 398.57 is: 595.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    480.78 : 717.89 = 398.57 : x
  2. Step 2: Convert to fraction form
    480.78/717.89 = 398.57/x
  3. Step 3: Cross multiply
    480.78x = 717.89 × 398.57
  4. Step 4: Simplify right side
    480.78x = 286,123.84
  5. Step 5: Solve for x
    x = 286,123.84/480.78
  6. Step 6: Final answer
    x = 595.12

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.