Home / 721.03-1,081.23-258.70

Finding the Fourth Proportional to 721.03, 1,081.23 and 258.70

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Solution

The fourth proportional to 721.03, 1,081.23 and 258.70 is: 387.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.03 : 1,081.23 = 258.70 : x
  2. Step 2: Convert to fraction form
    721.03/1,081.23 = 258.70/x
  3. Step 3: Cross multiply
    721.03x = 1,081.23 × 258.70
  4. Step 4: Simplify right side
    721.03x = 279,714.20
  5. Step 5: Solve for x
    x = 279,714.20/721.03
  6. Step 6: Final answer
    x = 387.94

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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.