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Finding the Fourth Proportional to 438.28, 605.10 and 305.47

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Solution

The fourth proportional to 438.28, 605.10 and 305.47 is: 421.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.28 : 605.10 = 305.47 : x
  2. Step 2: Convert to fraction form
    438.28/605.10 = 305.47/x
  3. Step 3: Cross multiply
    438.28x = 605.10 × 305.47
  4. Step 4: Simplify right side
    438.28x = 184,839.90
  5. Step 5: Solve for x
    x = 184,839.90/438.28
  6. Step 6: Final answer
    x = 421.74

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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.