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Finding the Fourth Proportional to 638.08, 955.80 and 515.77

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Solution

The fourth proportional to 638.08, 955.80 and 515.77 is: 772.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.08 : 955.80 = 515.77 : x
  2. Step 2: Convert to fraction form
    638.08/955.80 = 515.77/x
  3. Step 3: Cross multiply
    638.08x = 955.80 × 515.77
  4. Step 4: Simplify right side
    638.08x = 492,970.58
  5. Step 5: Solve for x
    x = 492,970.58/638.08
  6. Step 6: Final answer
    x = 772.59

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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.