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Finding the Fourth Proportional to 499.61, 688.77 and 421.25

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Solution

The fourth proportional to 499.61, 688.77 and 421.25 is: 580.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.61 : 688.77 = 421.25 : x
  2. Step 2: Convert to fraction form
    499.61/688.77 = 421.25/x
  3. Step 3: Cross multiply
    499.61x = 688.77 × 421.25
  4. Step 4: Simplify right side
    499.61x = 290,140.92
  5. Step 5: Solve for x
    x = 290,140.92/499.61
  6. Step 6: Final answer
    x = 580.74

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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.