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Finding the Fourth Proportional to 853.20, 1,279.40 and 305.18

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Solution

The fourth proportional to 853.20, 1,279.40 and 305.18 is: 457.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    853.20 : 1,279.40 = 305.18 : x
  2. Step 2: Convert to fraction form
    853.20/1,279.40 = 305.18/x
  3. Step 3: Cross multiply
    853.20x = 1,279.40 × 305.18
  4. Step 4: Simplify right side
    853.20x = 390,439.37
  5. Step 5: Solve for x
    x = 390,439.37/853.20
  6. Step 6: Final answer
    x = 457.62

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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.