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Finding the Fourth Proportional to 643.25, 964.90 and 277.79

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Solution

The fourth proportional to 643.25, 964.90 and 277.79 is: 416.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.25 : 964.90 = 277.79 : x
  2. Step 2: Convert to fraction form
    643.25/964.90 = 277.79/x
  3. Step 3: Cross multiply
    643.25x = 964.90 × 277.79
  4. Step 4: Simplify right side
    643.25x = 268,039.57
  5. Step 5: Solve for x
    x = 268,039.57/643.25
  6. Step 6: Final answer
    x = 416.70

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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.