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Finding the Fourth Proportional to 620.80, 929.37 and 459.21

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Solution

The fourth proportional to 620.80, 929.37 and 459.21 is: 687.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.80 : 929.37 = 459.21 : x
  2. Step 2: Convert to fraction form
    620.80/929.37 = 459.21/x
  3. Step 3: Cross multiply
    620.80x = 929.37 × 459.21
  4. Step 4: Simplify right side
    620.80x = 426,776.00
  5. Step 5: Solve for x
    x = 426,776.00/620.80
  6. Step 6: Final answer
    x = 687.46

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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.