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Finding the Fourth Proportional to 643.24, 881.89 and 631.57

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Solution

The fourth proportional to 643.24, 881.89 and 631.57 is: 865.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.24 : 881.89 = 631.57 : x
  2. Step 2: Convert to fraction form
    643.24/881.89 = 631.57/x
  3. Step 3: Cross multiply
    643.24x = 881.89 × 631.57
  4. Step 4: Simplify right side
    643.24x = 556,975.27
  5. Step 5: Solve for x
    x = 556,975.27/643.24
  6. Step 6: Final answer
    x = 865.89

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.