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Finding the Fourth Proportional to 405.90, 608.70 and 200.40

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Solution

The fourth proportional to 405.90, 608.70 and 200.40 is: 300.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.90 : 608.70 = 200.40 : x
  2. Step 2: Convert to fraction form
    405.90/608.70 = 200.40/x
  3. Step 3: Cross multiply
    405.90x = 608.70 × 200.40
  4. Step 4: Simplify right side
    405.90x = 121,983.48
  5. Step 5: Solve for x
    x = 121,983.48/405.90
  6. Step 6: Final answer
    x = 300.53

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.