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Finding the Fourth Proportional to 628.51, 867.21 and 395.50

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Solution

The fourth proportional to 628.51, 867.21 and 395.50 is: 545.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.51 : 867.21 = 395.50 : x
  2. Step 2: Convert to fraction form
    628.51/867.21 = 395.50/x
  3. Step 3: Cross multiply
    628.51x = 867.21 × 395.50
  4. Step 4: Simplify right side
    628.51x = 342,981.56
  5. Step 5: Solve for x
    x = 342,981.56/628.51
  6. Step 6: Final answer
    x = 545.71

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.