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Finding the Fourth Proportional to 489.55, 676.02 and 315.20

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Solution

The fourth proportional to 489.55, 676.02 and 315.20 is: 435.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.55 : 676.02 = 315.20 : x
  2. Step 2: Convert to fraction form
    489.55/676.02 = 315.20/x
  3. Step 3: Cross multiply
    489.55x = 676.02 × 315.20
  4. Step 4: Simplify right side
    489.55x = 213,081.50
  5. Step 5: Solve for x
    x = 213,081.50/489.55
  6. Step 6: Final answer
    x = 435.26

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.