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Finding the Fourth Proportional to 628.80, 936.10 and 621.78

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Solution

The fourth proportional to 628.80, 936.10 and 621.78 is: 925.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.80 : 936.10 = 621.78 : x
  2. Step 2: Convert to fraction form
    628.80/936.10 = 621.78/x
  3. Step 3: Cross multiply
    628.80x = 936.10 × 621.78
  4. Step 4: Simplify right side
    628.80x = 582,048.26
  5. Step 5: Solve for x
    x = 582,048.26/628.80
  6. Step 6: Final answer
    x = 925.65

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.