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Finding the Fourth Proportional to 638.78, 958.28 and 228.16

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Solution

The fourth proportional to 638.78, 958.28 and 228.16 is: 342.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.78 : 958.28 = 228.16 : x
  2. Step 2: Convert to fraction form
    638.78/958.28 = 228.16/x
  3. Step 3: Cross multiply
    638.78x = 958.28 × 228.16
  4. Step 4: Simplify right side
    638.78x = 218,641.16
  5. Step 5: Solve for x
    x = 218,641.16/638.78
  6. Step 6: Final answer
    x = 342.28

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.