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Finding the Fourth Proportional to 642.98, 964.20 and 313.82

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Solution

The fourth proportional to 642.98, 964.20 and 313.82 is: 470.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.98 : 964.20 = 313.82 : x
  2. Step 2: Convert to fraction form
    642.98/964.20 = 313.82/x
  3. Step 3: Cross multiply
    642.98x = 964.20 × 313.82
  4. Step 4: Simplify right side
    642.98x = 302,585.24
  5. Step 5: Solve for x
    x = 302,585.24/642.98
  6. Step 6: Final answer
    x = 470.60

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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.