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Finding the Fourth Proportional to 688.38, 949.72 and 389.59

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Solution

The fourth proportional to 688.38, 949.72 and 389.59 is: 537.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.38 : 949.72 = 389.59 : x
  2. Step 2: Convert to fraction form
    688.38/949.72 = 389.59/x
  3. Step 3: Cross multiply
    688.38x = 949.72 × 389.59
  4. Step 4: Simplify right side
    688.38x = 370,001.41
  5. Step 5: Solve for x
    x = 370,001.41/688.38
  6. Step 6: Final answer
    x = 537.50

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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.