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Finding the Fourth Proportional to 688.52, 950.15 and 393.78

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Solution

The fourth proportional to 688.52, 950.15 and 393.78 is: 543.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.52 : 950.15 = 393.78 : x
  2. Step 2: Convert to fraction form
    688.52/950.15 = 393.78/x
  3. Step 3: Cross multiply
    688.52x = 950.15 × 393.78
  4. Step 4: Simplify right side
    688.52x = 374,148.10
  5. Step 5: Solve for x
    x = 374,148.10/688.52
  6. Step 6: Final answer
    x = 543.41

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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.