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Finding the Fourth Proportional to 630.78, 946.38 and 445.70

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Solution

The fourth proportional to 630.78, 946.38 and 445.70 is: 668.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.78 : 946.38 = 445.70 : x
  2. Step 2: Convert to fraction form
    630.78/946.38 = 445.70/x
  3. Step 3: Cross multiply
    630.78x = 946.38 × 445.70
  4. Step 4: Simplify right side
    630.78x = 421,796.83
  5. Step 5: Solve for x
    x = 421,796.83/630.78
  6. Step 6: Final answer
    x = 668.69

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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.