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Finding the Fourth Proportional to 643.19, 964.86 and 253.19

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Solution

The fourth proportional to 643.19, 964.86 and 253.19 is: 379.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.19 : 964.86 = 253.19 : x
  2. Step 2: Convert to fraction form
    643.19/964.86 = 253.19/x
  3. Step 3: Cross multiply
    643.19x = 964.86 × 253.19
  4. Step 4: Simplify right side
    643.19x = 244,292.90
  5. Step 5: Solve for x
    x = 244,292.90/643.19
  6. Step 6: Final answer
    x = 379.81

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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.