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Finding the Fourth Proportional to 651.40, 978.45 and 628.45

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Solution

The fourth proportional to 651.40, 978.45 and 628.45 is: 943.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.40 : 978.45 = 628.45 : x
  2. Step 2: Convert to fraction form
    651.40/978.45 = 628.45/x
  3. Step 3: Cross multiply
    651.40x = 978.45 × 628.45
  4. Step 4: Simplify right side
    651.40x = 614,906.90
  5. Step 5: Solve for x
    x = 614,906.90/651.40
  6. Step 6: Final answer
    x = 943.98

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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.