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Finding the Fourth Proportional to 647.85, 969.71 and 339.28

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Solution

The fourth proportional to 647.85, 969.71 and 339.28 is: 507.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.85 : 969.71 = 339.28 : x
  2. Step 2: Convert to fraction form
    647.85/969.71 = 339.28/x
  3. Step 3: Cross multiply
    647.85x = 969.71 × 339.28
  4. Step 4: Simplify right side
    647.85x = 328,999.09
  5. Step 5: Solve for x
    x = 328,999.09/647.85
  6. Step 6: Final answer
    x = 507.83

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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.