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Finding the Fourth Proportional to 643.80, 965.93 and 253.83

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Solution

The fourth proportional to 643.80, 965.93 and 253.83 is: 380.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.80 : 965.93 = 253.83 : x
  2. Step 2: Convert to fraction form
    643.80/965.93 = 253.83/x
  3. Step 3: Cross multiply
    643.80x = 965.93 × 253.83
  4. Step 4: Simplify right side
    643.80x = 245,184.36
  5. Step 5: Solve for x
    x = 245,184.36/643.80
  6. Step 6: Final answer
    x = 380.84

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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.