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Finding the Fourth Proportional to 402.85, 555.90 and 228.20

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Solution

The fourth proportional to 402.85, 555.90 and 228.20 is: 314.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.85 : 555.90 = 228.20 : x
  2. Step 2: Convert to fraction form
    402.85/555.90 = 228.20/x
  3. Step 3: Cross multiply
    402.85x = 555.90 × 228.20
  4. Step 4: Simplify right side
    402.85x = 126,856.38
  5. Step 5: Solve for x
    x = 126,856.38/402.85
  6. Step 6: Final answer
    x = 314.90

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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.