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Finding the Fourth Proportional to 540.40, 808.78 and 449.28

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Solution

The fourth proportional to 540.40, 808.78 and 449.28 is: 672.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.40 : 808.78 = 449.28 : x
  2. Step 2: Convert to fraction form
    540.40/808.78 = 449.28/x
  3. Step 3: Cross multiply
    540.40x = 808.78 × 449.28
  4. Step 4: Simplify right side
    540.40x = 363,362.39
  5. Step 5: Solve for x
    x = 363,362.39/540.40
  6. Step 6: Final answer
    x = 672.40

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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.