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Finding the Fourth Proportional to 405.32, 559.40 and 306.90

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Solution

The fourth proportional to 405.32, 559.40 and 306.90 is: 423.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.32 : 559.40 = 306.90 : x
  2. Step 2: Convert to fraction form
    405.32/559.40 = 306.90/x
  3. Step 3: Cross multiply
    405.32x = 559.40 × 306.90
  4. Step 4: Simplify right side
    405.32x = 171,679.86
  5. Step 5: Solve for x
    x = 171,679.86/405.32
  6. Step 6: Final answer
    x = 423.57

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.