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Finding the Fourth Proportional to 419.42, 579.41 and 309.50

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Solution

The fourth proportional to 419.42, 579.41 and 309.50 is: 427.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.42 : 579.41 = 309.50 : x
  2. Step 2: Convert to fraction form
    419.42/579.41 = 309.50/x
  3. Step 3: Cross multiply
    419.42x = 579.41 × 309.50
  4. Step 4: Simplify right side
    419.42x = 179,325.70
  5. Step 5: Solve for x
    x = 179,325.70/419.42
  6. Step 6: Final answer
    x = 427.56

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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.