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Finding the Fourth Proportional to 403.80, 605.80 and 208.74

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Solution

The fourth proportional to 403.80, 605.80 and 208.74 is: 313.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.80 : 605.80 = 208.74 : x
  2. Step 2: Convert to fraction form
    403.80/605.80 = 208.74/x
  3. Step 3: Cross multiply
    403.80x = 605.80 × 208.74
  4. Step 4: Simplify right side
    403.80x = 126,454.69
  5. Step 5: Solve for x
    x = 126,454.69/403.80
  6. Step 6: Final answer
    x = 313.16

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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.