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Finding the Fourth Proportional to 403.45, 605.15 and 257.34

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Solution

The fourth proportional to 403.45, 605.15 and 257.34 is: 386.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.45 : 605.15 = 257.34 : x
  2. Step 2: Convert to fraction form
    403.45/605.15 = 257.34/x
  3. Step 3: Cross multiply
    403.45x = 605.15 × 257.34
  4. Step 4: Simplify right side
    403.45x = 155,729.30
  5. Step 5: Solve for x
    x = 155,729.30/403.45
  6. Step 6: Final answer
    x = 386.00

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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.