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Finding the Fourth Proportional to 642.73, 881.18 and 631.05

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Solution

The fourth proportional to 642.73, 881.18 and 631.05 is: 865.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.73 : 881.18 = 631.05 : x
  2. Step 2: Convert to fraction form
    642.73/881.18 = 631.05/x
  3. Step 3: Cross multiply
    642.73x = 881.18 × 631.05
  4. Step 4: Simplify right side
    642.73x = 556,065.48
  5. Step 5: Solve for x
    x = 556,065.48/642.73
  6. Step 6: Final answer
    x = 865.17

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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.