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Finding the Fourth Proportional to 826.32, 1,239 and 339.72

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Solution

The fourth proportional to 826.32, 1,239 and 339.72 is: 509.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    826.32 : 1,239 = 339.72 : x
  2. Step 2: Convert to fraction form
    826.32/1,239 = 339.72/x
  3. Step 3: Cross multiply
    826.32x = 1,239 × 339.72
  4. Step 4: Simplify right side
    826.32x = 420,913.08
  5. Step 5: Solve for x
    x = 420,913.08/826.32
  6. Step 6: Final answer
    x = 509.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.