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Finding the Fourth Proportional to 641.81, 961.88 and 290.15

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Solution

The fourth proportional to 641.81, 961.88 and 290.15 is: 434.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.81 : 961.88 = 290.15 : x
  2. Step 2: Convert to fraction form
    641.81/961.88 = 290.15/x
  3. Step 3: Cross multiply
    641.81x = 961.88 × 290.15
  4. Step 4: Simplify right side
    641.81x = 279,088.03
  5. Step 5: Solve for x
    x = 279,088.03/641.81
  6. Step 6: Final answer
    x = 434.85

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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.