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Finding the Fourth Proportional to 688.12, 949.29 and 439.31

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Solution

The fourth proportional to 688.12, 949.29 and 439.31 is: 606.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.12 : 949.29 = 439.31 : x
  2. Step 2: Convert to fraction form
    688.12/949.29 = 439.31/x
  3. Step 3: Cross multiply
    688.12x = 949.29 × 439.31
  4. Step 4: Simplify right side
    688.12x = 417,033.32
  5. Step 5: Solve for x
    x = 417,033.32/688.12
  6. Step 6: Final answer
    x = 606.05

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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.