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Finding the Fourth Proportional to 618.30, 928.26 and 386.55

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Solution

The fourth proportional to 618.30, 928.26 and 386.55 is: 580.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.30 : 928.26 = 386.55 : x
  2. Step 2: Convert to fraction form
    618.30/928.26 = 386.55/x
  3. Step 3: Cross multiply
    618.30x = 928.26 × 386.55
  4. Step 4: Simplify right side
    618.30x = 358,818.90
  5. Step 5: Solve for x
    x = 358,818.90/618.30
  6. Step 6: Final answer
    x = 580.33

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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.