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Finding the Fourth Proportional to 688.05, 949.35 and 439.28

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Solution

The fourth proportional to 688.05, 949.35 and 439.28 is: 606.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.05 : 949.35 = 439.28 : x
  2. Step 2: Convert to fraction form
    688.05/949.35 = 439.28/x
  3. Step 3: Cross multiply
    688.05x = 949.35 × 439.28
  4. Step 4: Simplify right side
    688.05x = 417,025.72
  5. Step 5: Solve for x
    x = 417,025.72/688.05
  6. Step 6: Final answer
    x = 606.10

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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.