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Finding the Fourth Proportional to 320.36, 442.28 and 257.18

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Solution

The fourth proportional to 320.36, 442.28 and 257.18 is: 355.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.36 : 442.28 = 257.18 : x
  2. Step 2: Convert to fraction form
    320.36/442.28 = 257.18/x
  3. Step 3: Cross multiply
    320.36x = 442.28 × 257.18
  4. Step 4: Simplify right side
    320.36x = 113,744.28
  5. Step 5: Solve for x
    x = 113,744.28/320.36
  6. Step 6: Final answer
    x = 355.05

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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.