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Finding the Fourth Proportional to 618.65, 854.05 and 478.45

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Solution

The fourth proportional to 618.65, 854.05 and 478.45 is: 660.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.65 : 854.05 = 478.45 : x
  2. Step 2: Convert to fraction form
    618.65/854.05 = 478.45/x
  3. Step 3: Cross multiply
    618.65x = 854.05 × 478.45
  4. Step 4: Simplify right side
    618.65x = 408,620.22
  5. Step 5: Solve for x
    x = 408,620.22/618.65
  6. Step 6: Final answer
    x = 660.50

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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.