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Finding the Fourth Proportional to 499.86, 689.91 and 322.70

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Solution

The fourth proportional to 499.86, 689.91 and 322.70 is: 445.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.86 : 689.91 = 322.70 : x
  2. Step 2: Convert to fraction form
    499.86/689.91 = 322.70/x
  3. Step 3: Cross multiply
    499.86x = 689.91 × 322.70
  4. Step 4: Simplify right side
    499.86x = 222,630.51
  5. Step 5: Solve for x
    x = 222,630.51/499.86
  6. Step 6: Final answer
    x = 445.39

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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.