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Finding the Fourth Proportional to 491.20, 737.40 and 389.75

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Solution

The fourth proportional to 491.20, 737.40 and 389.75 is: 585.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.20 : 737.40 = 389.75 : x
  2. Step 2: Convert to fraction form
    491.20/737.40 = 389.75/x
  3. Step 3: Cross multiply
    491.20x = 737.40 × 389.75
  4. Step 4: Simplify right side
    491.20x = 287,399.42
  5. Step 5: Solve for x
    x = 287,399.42/491.20
  6. Step 6: Final answer
    x = 585.10

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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.