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Finding the Fourth Proportional to 403.70, 605.15 and 208.80

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Solution

The fourth proportional to 403.70, 605.15 and 208.80 is: 312.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.70 : 605.15 = 208.80 : x
  2. Step 2: Convert to fraction form
    403.70/605.15 = 208.80/x
  3. Step 3: Cross multiply
    403.70x = 605.15 × 208.80
  4. Step 4: Simplify right side
    403.70x = 126,352.29
  5. Step 5: Solve for x
    x = 126,352.29/403.70
  6. Step 6: Final answer
    x = 312.99

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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.