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Finding the Fourth Proportional to 618.80, 928.20 and 400.10

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Solution

The fourth proportional to 618.80, 928.20 and 400.10 is: 600.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.80 : 928.20 = 400.10 : x
  2. Step 2: Convert to fraction form
    618.80/928.20 = 400.10/x
  3. Step 3: Cross multiply
    618.80x = 928.20 × 400.10
  4. Step 4: Simplify right side
    618.80x = 371,372.82
  5. Step 5: Solve for x
    x = 371,372.82/618.80
  6. Step 6: Final answer
    x = 600.15

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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.