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Finding the Fourth Proportional to 643.77, 965.66 and 258.75

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Solution

The fourth proportional to 643.77, 965.66 and 258.75 is: 388.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.77 : 965.66 = 258.75 : x
  2. Step 2: Convert to fraction form
    643.77/965.66 = 258.75/x
  3. Step 3: Cross multiply
    643.77x = 965.66 × 258.75
  4. Step 4: Simplify right side
    643.77x = 249,863.23
  5. Step 5: Solve for x
    x = 249,863.23/643.77
  6. Step 6: Final answer
    x = 388.13

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Half scale
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Double scale
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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.