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Finding the Fourth Proportional to 643.24, 964.32 and 258.28

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Solution

The fourth proportional to 643.24, 964.32 and 258.28 is: 387.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.24 : 964.32 = 258.28 : x
  2. Step 2: Convert to fraction form
    643.24/964.32 = 258.28/x
  3. Step 3: Cross multiply
    643.24x = 964.32 × 258.28
  4. Step 4: Simplify right side
    643.24x = 249,064.57
  5. Step 5: Solve for x
    x = 249,064.57/643.24
  6. Step 6: Final answer
    x = 387.20

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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.