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Finding the Fourth Proportional to 618.80, 864.70 and 618.80

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Solution

The fourth proportional to 618.80, 864.70 and 618.80 is: 864.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.80 : 864.70 = 618.80 : x
  2. Step 2: Convert to fraction form
    618.80/864.70 = 618.80/x
  3. Step 3: Cross multiply
    618.80x = 864.70 × 618.80
  4. Step 4: Simplify right side
    618.80x = 535,076.36
  5. Step 5: Solve for x
    x = 535,076.36/618.80
  6. Step 6: Final answer
    x = 864.70

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.