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Finding the Fourth Proportional to 642.34, 963.42 and 257.50

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Solution

The fourth proportional to 642.34, 963.42 and 257.50 is: 386.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.34 : 963.42 = 257.50 : x
  2. Step 2: Convert to fraction form
    642.34/963.42 = 257.50/x
  3. Step 3: Cross multiply
    642.34x = 963.42 × 257.50
  4. Step 4: Simplify right side
    642.34x = 248,080.65
  5. Step 5: Solve for x
    x = 248,080.65/642.34
  6. Step 6: Final answer
    x = 386.21

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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.