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Finding the Fourth Proportional to 418.72, 630.40 and 328.60

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Solution

The fourth proportional to 418.72, 630.40 and 328.60 is: 494.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.72 : 630.40 = 328.60 : x
  2. Step 2: Convert to fraction form
    418.72/630.40 = 328.60/x
  3. Step 3: Cross multiply
    418.72x = 630.40 × 328.60
  4. Step 4: Simplify right side
    418.72x = 207,149.44
  5. Step 5: Solve for x
    x = 207,149.44/418.72
  6. Step 6: Final answer
    x = 494.72

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.