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Finding the Fourth Proportional to 643.85, 965.36 and 424.22

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Solution

The fourth proportional to 643.85, 965.36 and 424.22 is: 636.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.85 : 965.36 = 424.22 : x
  2. Step 2: Convert to fraction form
    643.85/965.36 = 424.22/x
  3. Step 3: Cross multiply
    643.85x = 965.36 × 424.22
  4. Step 4: Simplify right side
    643.85x = 409,518.07
  5. Step 5: Solve for x
    x = 409,518.07/643.85
  6. Step 6: Final answer
    x = 636.05

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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.