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Finding the Fourth Proportional to 651.60, 978.12 and 612

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Solution

The fourth proportional to 651.60, 978.12 and 612 is: 918.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.60 : 978.12 = 612 : x
  2. Step 2: Convert to fraction form
    651.60/978.12 = 612/x
  3. Step 3: Cross multiply
    651.60x = 978.12 × 612
  4. Step 4: Simplify right side
    651.60x = 598,609.44
  5. Step 5: Solve for x
    x = 598,609.44/651.60
  6. Step 6: Final answer
    x = 918.68

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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.