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Finding the Fourth Proportional to 253.39, 380.09 and 70.78

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Solution

The fourth proportional to 253.39, 380.09 and 70.78 is: 106.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.39 : 380.09 = 70.78 : x
  2. Step 2: Convert to fraction form
    253.39/380.09 = 70.78/x
  3. Step 3: Cross multiply
    253.39x = 380.09 × 70.78
  4. Step 4: Simplify right side
    253.39x = 26,902.77
  5. Step 5: Solve for x
    x = 26,902.77/253.39
  6. Step 6: Final answer
    x = 106.17

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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.