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Finding the Fourth Proportional to 399.30, 599.20 and 216.84

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Solution

The fourth proportional to 399.30, 599.20 and 216.84 is: 325.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.30 : 599.20 = 216.84 : x
  2. Step 2: Convert to fraction form
    399.30/599.20 = 216.84/x
  3. Step 3: Cross multiply
    399.30x = 599.20 × 216.84
  4. Step 4: Simplify right side
    399.30x = 129,930.53
  5. Step 5: Solve for x
    x = 129,930.53/399.30
  6. Step 6: Final answer
    x = 325.40

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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.