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Finding the Fourth Proportional to 642.89, 964.64 and 277.79

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Solution

The fourth proportional to 642.89, 964.64 and 277.79 is: 416.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.89 : 964.64 = 277.79 : x
  2. Step 2: Convert to fraction form
    642.89/964.64 = 277.79/x
  3. Step 3: Cross multiply
    642.89x = 964.64 × 277.79
  4. Step 4: Simplify right side
    642.89x = 267,963.22
  5. Step 5: Solve for x
    x = 267,963.22/642.89
  6. Step 6: Final answer
    x = 416.81

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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.