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Finding the Fourth Proportional to 688.20, 949.82 and 393.56

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Solution

The fourth proportional to 688.20, 949.82 and 393.56 is: 543.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.20 : 949.82 = 393.56 : x
  2. Step 2: Convert to fraction form
    688.20/949.82 = 393.56/x
  3. Step 3: Cross multiply
    688.20x = 949.82 × 393.56
  4. Step 4: Simplify right side
    688.20x = 373,811.16
  5. Step 5: Solve for x
    x = 373,811.16/688.20
  6. Step 6: Final answer
    x = 543.17

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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.