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Finding the Fourth Proportional to 636.80, 956.21 and 513.81

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Solution

The fourth proportional to 636.80, 956.21 and 513.81 is: 771.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.80 : 956.21 = 513.81 : x
  2. Step 2: Convert to fraction form
    636.80/956.21 = 513.81/x
  3. Step 3: Cross multiply
    636.80x = 956.21 × 513.81
  4. Step 4: Simplify right side
    636.80x = 491,307.69
  5. Step 5: Solve for x
    x = 491,307.69/636.80
  6. Step 6: Final answer
    x = 771.53

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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.