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Finding the Fourth Proportional to 742.82, 1,025.09 and 428.15

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Solution

The fourth proportional to 742.82, 1,025.09 and 428.15 is: 590.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    742.82 : 1,025.09 = 428.15 : x
  2. Step 2: Convert to fraction form
    742.82/1,025.09 = 428.15/x
  3. Step 3: Cross multiply
    742.82x = 1,025.09 × 428.15
  4. Step 4: Simplify right side
    742.82x = 438,885.02
  5. Step 5: Solve for x
    x = 438,885.02/742.82
  6. Step 6: Final answer
    x = 590.84

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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.