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Finding the Fourth Proportional to 405.20, 607.65 and 145.19

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Solution

The fourth proportional to 405.20, 607.65 and 145.19 is: 217.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.20 : 607.65 = 145.19 : x
  2. Step 2: Convert to fraction form
    405.20/607.65 = 145.19/x
  3. Step 3: Cross multiply
    405.20x = 607.65 × 145.19
  4. Step 4: Simplify right side
    405.20x = 88,226.49
  5. Step 5: Solve for x
    x = 88,226.49/405.20
  6. Step 6: Final answer
    x = 217.73

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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.