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Finding the Fourth Proportional to 643.66, 965.85 and 259.18

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Solution

The fourth proportional to 643.66, 965.85 and 259.18 is: 388.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.66 : 965.85 = 259.18 : x
  2. Step 2: Convert to fraction form
    643.66/965.85 = 259.18/x
  3. Step 3: Cross multiply
    643.66x = 965.85 × 259.18
  4. Step 4: Simplify right side
    643.66x = 250,329.00
  5. Step 5: Solve for x
    x = 250,329.00/643.66
  6. Step 6: Final answer
    x = 388.91

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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.