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Finding the Fourth Proportional to 399.72, 599.02 and 318.20

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Solution

The fourth proportional to 399.72, 599.02 and 318.20 is: 476.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.72 : 599.02 = 318.20 : x
  2. Step 2: Convert to fraction form
    399.72/599.02 = 318.20/x
  3. Step 3: Cross multiply
    399.72x = 599.02 × 318.20
  4. Step 4: Simplify right side
    399.72x = 190,608.16
  5. Step 5: Solve for x
    x = 190,608.16/399.72
  6. Step 6: Final answer
    x = 476.85

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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.