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Finding the Fourth Proportional to 405.05, 603.56 and 385.40

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Solution

The fourth proportional to 405.05, 603.56 and 385.40 is: 574.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.05 : 603.56 = 385.40 : x
  2. Step 2: Convert to fraction form
    405.05/603.56 = 385.40/x
  3. Step 3: Cross multiply
    405.05x = 603.56 × 385.40
  4. Step 4: Simplify right side
    405.05x = 232,611.61
  5. Step 5: Solve for x
    x = 232,611.61/405.05
  6. Step 6: Final answer
    x = 574.29

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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.