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Finding the Fourth Proportional to 618.85, 928.81 and 388.19

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Solution

The fourth proportional to 618.85, 928.81 and 388.19 is: 582.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.85 : 928.81 = 388.19 : x
  2. Step 2: Convert to fraction form
    618.85/928.81 = 388.19/x
  3. Step 3: Cross multiply
    618.85x = 928.81 × 388.19
  4. Step 4: Simplify right side
    618.85x = 360,548.17
  5. Step 5: Solve for x
    x = 360,548.17/618.85
  6. Step 6: Final answer
    x = 582.61

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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.