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Finding the Fourth Proportional to 621.39, 856.53 and 496.65

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Solution

The fourth proportional to 621.39, 856.53 and 496.65 is: 684.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.39 : 856.53 = 496.65 : x
  2. Step 2: Convert to fraction form
    621.39/856.53 = 496.65/x
  3. Step 3: Cross multiply
    621.39x = 856.53 × 496.65
  4. Step 4: Simplify right side
    621.39x = 425,395.62
  5. Step 5: Solve for x
    x = 425,395.62/621.39
  6. Step 6: Final answer
    x = 684.59

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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.