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Finding the Fourth Proportional to 405.25, 559.14 and 305.71

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Solution

The fourth proportional to 405.25, 559.14 and 305.71 is: 421.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.25 : 559.14 = 305.71 : x
  2. Step 2: Convert to fraction form
    405.25/559.14 = 305.71/x
  3. Step 3: Cross multiply
    405.25x = 559.14 × 305.71
  4. Step 4: Simplify right side
    405.25x = 170,934.69
  5. Step 5: Solve for x
    x = 170,934.69/405.25
  6. Step 6: Final answer
    x = 421.80

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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.