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Finding the Fourth Proportional to 618.90, 928.17 and 228.90

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Solution

The fourth proportional to 618.90, 928.17 and 228.90 is: 343.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.90 : 928.17 = 228.90 : x
  2. Step 2: Convert to fraction form
    618.90/928.17 = 228.90/x
  3. Step 3: Cross multiply
    618.90x = 928.17 × 228.90
  4. Step 4: Simplify right side
    618.90x = 212,458.11
  5. Step 5: Solve for x
    x = 212,458.11/618.90
  6. Step 6: Final answer
    x = 343.28

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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.