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Finding the Fourth Proportional to 438.30, 605.12 and 291.20

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Solution

The fourth proportional to 438.30, 605.12 and 291.20 is: 402.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.30 : 605.12 = 291.20 : x
  2. Step 2: Convert to fraction form
    438.30/605.12 = 291.20/x
  3. Step 3: Cross multiply
    438.30x = 605.12 × 291.20
  4. Step 4: Simplify right side
    438.30x = 176,206.46
  5. Step 5: Solve for x
    x = 176,206.46/438.30
  6. Step 6: Final answer
    x = 402.02

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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.