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Finding the Fourth Proportional to 405.65, 559.98 and 306.11

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Solution

The fourth proportional to 405.65, 559.98 and 306.11 is: 422.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.65 : 559.98 = 306.11 : x
  2. Step 2: Convert to fraction form
    405.65/559.98 = 306.11/x
  3. Step 3: Cross multiply
    405.65x = 559.98 × 306.11
  4. Step 4: Simplify right side
    405.65x = 171,412.68
  5. Step 5: Solve for x
    x = 171,412.68/405.65
  6. Step 6: Final answer
    x = 422.57

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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.