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Finding the Fourth Proportional to 699.75, 965.82 and 420.15

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Solution

The fourth proportional to 699.75, 965.82 and 420.15 is: 579.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    699.75 : 965.82 = 420.15 : x
  2. Step 2: Convert to fraction form
    699.75/965.82 = 420.15/x
  3. Step 3: Cross multiply
    699.75x = 965.82 × 420.15
  4. Step 4: Simplify right side
    699.75x = 405,784.44
  5. Step 5: Solve for x
    x = 405,784.44/699.75
  6. Step 6: Final answer
    x = 579.90

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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.