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Finding the Fourth Proportional to 643.57, 965.35 and 259.09

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Solution

The fourth proportional to 643.57, 965.35 and 259.09 is: 388.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.57 : 965.35 = 259.09 : x
  2. Step 2: Convert to fraction form
    643.57/965.35 = 259.09/x
  3. Step 3: Cross multiply
    643.57x = 965.35 × 259.09
  4. Step 4: Simplify right side
    643.57x = 250,107.70
  5. Step 5: Solve for x
    x = 250,107.70/643.57
  6. Step 6: Final answer
    x = 388.63

Related Problems

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Half scale
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Double scale
Find fourth proportional to 644.57, 966.85 and 260.09
Similar ratio
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1.5x scale

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.