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Finding the Fourth Proportional to 612.80, 917.40 and 369.80

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Solution

The fourth proportional to 612.80, 917.40 and 369.80 is: 553.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.80 : 917.40 = 369.80 : x
  2. Step 2: Convert to fraction form
    612.80/917.40 = 369.80/x
  3. Step 3: Cross multiply
    612.80x = 917.40 × 369.80
  4. Step 4: Simplify right side
    612.80x = 339,254.52
  5. Step 5: Solve for x
    x = 339,254.52/612.80
  6. Step 6: Final answer
    x = 553.61

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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.