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Finding the Fourth Proportional to 651.90, 978.09 and 343.76

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Solution

The fourth proportional to 651.90, 978.09 and 343.76 is: 515.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.90 : 978.09 = 343.76 : x
  2. Step 2: Convert to fraction form
    651.90/978.09 = 343.76/x
  3. Step 3: Cross multiply
    651.90x = 978.09 × 343.76
  4. Step 4: Simplify right side
    651.90x = 336,226.50
  5. Step 5: Solve for x
    x = 336,226.50/651.90
  6. Step 6: Final answer
    x = 515.76

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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.