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Finding the Fourth Proportional to 407.80, 607.49 and 398.20

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Solution

The fourth proportional to 407.80, 607.49 and 398.20 is: 593.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    407.80 : 607.49 = 398.20 : x
  2. Step 2: Convert to fraction form
    407.80/607.49 = 398.20/x
  3. Step 3: Cross multiply
    407.80x = 607.49 × 398.20
  4. Step 4: Simplify right side
    407.80x = 241,902.52
  5. Step 5: Solve for x
    x = 241,902.52/407.80
  6. Step 6: Final answer
    x = 593.19

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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.