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Finding the Fourth Proportional to 640.80, 961.38 and 202.05

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Solution

The fourth proportional to 640.80, 961.38 and 202.05 is: 303.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.80 : 961.38 = 202.05 : x
  2. Step 2: Convert to fraction form
    640.80/961.38 = 202.05/x
  3. Step 3: Cross multiply
    640.80x = 961.38 × 202.05
  4. Step 4: Simplify right side
    640.80x = 194,246.83
  5. Step 5: Solve for x
    x = 194,246.83/640.80
  6. Step 6: Final answer
    x = 303.13

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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.