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Finding the Fourth Proportional to 641.76, 885.66 and 379.80

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Solution

The fourth proportional to 641.76, 885.66 and 379.80 is: 524.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.76 : 885.66 = 379.80 : x
  2. Step 2: Convert to fraction form
    641.76/885.66 = 379.80/x
  3. Step 3: Cross multiply
    641.76x = 885.66 × 379.80
  4. Step 4: Simplify right side
    641.76x = 336,373.67
  5. Step 5: Solve for x
    x = 336,373.67/641.76
  6. Step 6: Final answer
    x = 524.14

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.