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Finding the Fourth Proportional to 647.60, 970.72 and 339.80

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Solution

The fourth proportional to 647.60, 970.72 and 339.80 is: 509.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.60 : 970.72 = 339.80 : x
  2. Step 2: Convert to fraction form
    647.60/970.72 = 339.80/x
  3. Step 3: Cross multiply
    647.60x = 970.72 × 339.80
  4. Step 4: Simplify right side
    647.60x = 329,850.66
  5. Step 5: Solve for x
    x = 329,850.66/647.60
  6. Step 6: Final answer
    x = 509.34

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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.