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Finding the Fourth Proportional to 403.79, 605.21 and 312.53

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Solution

The fourth proportional to 403.79, 605.21 and 312.53 is: 468.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.79 : 605.21 = 312.53 : x
  2. Step 2: Convert to fraction form
    403.79/605.21 = 312.53/x
  3. Step 3: Cross multiply
    403.79x = 605.21 × 312.53
  4. Step 4: Simplify right side
    403.79x = 189,141.69
  5. Step 5: Solve for x
    x = 189,141.69/403.79
  6. Step 6: Final answer
    x = 468.42

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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.