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Finding the Fourth Proportional to 612.80, 916.80 and 396.80

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Solution

The fourth proportional to 612.80, 916.80 and 396.80 is: 593.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.80 : 916.80 = 396.80 : x
  2. Step 2: Convert to fraction form
    612.80/916.80 = 396.80/x
  3. Step 3: Cross multiply
    612.80x = 916.80 × 396.80
  4. Step 4: Simplify right side
    612.80x = 363,786.24
  5. Step 5: Solve for x
    x = 363,786.24/612.80
  6. Step 6: Final answer
    x = 593.65

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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.