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Finding the Fourth Proportional to 687.72, 949.04 and 393.02

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Solution

The fourth proportional to 687.72, 949.04 and 393.02 is: 542.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.72 : 949.04 = 393.02 : x
  2. Step 2: Convert to fraction form
    687.72/949.04 = 393.02/x
  3. Step 3: Cross multiply
    687.72x = 949.04 × 393.02
  4. Step 4: Simplify right side
    687.72x = 372,991.70
  5. Step 5: Solve for x
    x = 372,991.70/687.72
  6. Step 6: Final answer
    x = 542.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.