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Finding the Fourth Proportional to 643.28, 962.40 and 540.72

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Solution

The fourth proportional to 643.28, 962.40 and 540.72 is: 808.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.28 : 962.40 = 540.72 : x
  2. Step 2: Convert to fraction form
    643.28/962.40 = 540.72/x
  3. Step 3: Cross multiply
    643.28x = 962.40 × 540.72
  4. Step 4: Simplify right side
    643.28x = 520,388.93
  5. Step 5: Solve for x
    x = 520,388.93/643.28
  6. Step 6: Final answer
    x = 808.96

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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.