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Finding the Fourth Proportional to 643.33, 965.36 and 253.61

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Solution

The fourth proportional to 643.33, 965.36 and 253.61 is: 380.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.33 : 965.36 = 253.61 : x
  2. Step 2: Convert to fraction form
    643.33/965.36 = 253.61/x
  3. Step 3: Cross multiply
    643.33x = 965.36 × 253.61
  4. Step 4: Simplify right side
    643.33x = 244,824.95
  5. Step 5: Solve for x
    x = 244,824.95/643.33
  6. Step 6: Final answer
    x = 380.56

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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.