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Finding the Fourth Proportional to 643.51, 965.81 and 319.24

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Solution

The fourth proportional to 643.51, 965.81 and 319.24 is: 479.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.51 : 965.81 = 319.24 : x
  2. Step 2: Convert to fraction form
    643.51/965.81 = 319.24/x
  3. Step 3: Cross multiply
    643.51x = 965.81 × 319.24
  4. Step 4: Simplify right side
    643.51x = 308,325.18
  5. Step 5: Solve for x
    x = 308,325.18/643.51
  6. Step 6: Final answer
    x = 479.13

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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.