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Finding the Fourth Proportional to 618.39, 927.80 and 387.45

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Solution

The fourth proportional to 618.39, 927.80 and 387.45 is: 581.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.39 : 927.80 = 387.45 : x
  2. Step 2: Convert to fraction form
    618.39/927.80 = 387.45/x
  3. Step 3: Cross multiply
    618.39x = 927.80 × 387.45
  4. Step 4: Simplify right side
    618.39x = 359,476.11
  5. Step 5: Solve for x
    x = 359,476.11/618.39
  6. Step 6: Final answer
    x = 581.31

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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.