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Finding the Fourth Proportional to 643.15, 964.78 and 277.95

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Solution

The fourth proportional to 643.15, 964.78 and 277.95 is: 416.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.15 : 964.78 = 277.95 : x
  2. Step 2: Convert to fraction form
    643.15/964.78 = 277.95/x
  3. Step 3: Cross multiply
    643.15x = 964.78 × 277.95
  4. Step 4: Simplify right side
    643.15x = 268,159.91
  5. Step 5: Solve for x
    x = 268,159.91/643.15
  6. Step 6: Final answer
    x = 416.95

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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.