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Finding the Fourth Proportional to 642.94, 964.45 and 258.19

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Solution

The fourth proportional to 642.94, 964.45 and 258.19 is: 387.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.94 : 964.45 = 258.19 : x
  2. Step 2: Convert to fraction form
    642.94/964.45 = 258.19/x
  3. Step 3: Cross multiply
    642.94x = 964.45 × 258.19
  4. Step 4: Simplify right side
    642.94x = 249,011.35
  5. Step 5: Solve for x
    x = 249,011.35/642.94
  6. Step 6: Final answer
    x = 387.30

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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.