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Finding the Fourth Proportional to 699.85, 965.71 and 420.07

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Solution

The fourth proportional to 699.85, 965.71 and 420.07 is: 579.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    699.85 : 965.71 = 420.07 : x
  2. Step 2: Convert to fraction form
    699.85/965.71 = 420.07/x
  3. Step 3: Cross multiply
    699.85x = 965.71 × 420.07
  4. Step 4: Simplify right side
    699.85x = 405,665.80
  5. Step 5: Solve for x
    x = 405,665.80/699.85
  6. Step 6: Final answer
    x = 579.65

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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.