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Finding the Fourth Proportional to 647.79, 971.47 and 339.58

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Solution

The fourth proportional to 647.79, 971.47 and 339.58 is: 509.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.79 : 971.47 = 339.58 : x
  2. Step 2: Convert to fraction form
    647.79/971.47 = 339.58/x
  3. Step 3: Cross multiply
    647.79x = 971.47 × 339.58
  4. Step 4: Simplify right side
    647.79x = 329,891.78
  5. Step 5: Solve for x
    x = 329,891.78/647.79
  6. Step 6: Final answer
    x = 509.26

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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.