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Finding the Fourth Proportional to 538.45, 807.93 and 408.40

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Solution

The fourth proportional to 538.45, 807.93 and 408.40 is: 612.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.45 : 807.93 = 408.40 : x
  2. Step 2: Convert to fraction form
    538.45/807.93 = 408.40/x
  3. Step 3: Cross multiply
    538.45x = 807.93 × 408.40
  4. Step 4: Simplify right side
    538.45x = 329,956.59
  5. Step 5: Solve for x
    x = 329,956.59/538.45
  6. Step 6: Final answer
    x = 612.79

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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.