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Finding the Fourth Proportional to 618.10, 821.42 and 618.10

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Solution

The fourth proportional to 618.10, 821.42 and 618.10 is: 821.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.10 : 821.42 = 618.10 : x
  2. Step 2: Convert to fraction form
    618.10/821.42 = 618.10/x
  3. Step 3: Cross multiply
    618.10x = 821.42 × 618.10
  4. Step 4: Simplify right side
    618.10x = 507,719.70
  5. Step 5: Solve for x
    x = 507,719.70/618.10
  6. Step 6: Final answer
    x = 821.42

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Why These Related Problems?

These problems maintain the same ratio (1.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.