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Finding the Fourth Proportional to 721.04, 1,081.18 and 309.95

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Solution

The fourth proportional to 721.04, 1,081.18 and 309.95 is: 464.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.04 : 1,081.18 = 309.95 : x
  2. Step 2: Convert to fraction form
    721.04/1,081.18 = 309.95/x
  3. Step 3: Cross multiply
    721.04x = 1,081.18 × 309.95
  4. Step 4: Simplify right side
    721.04x = 335,111.74
  5. Step 5: Solve for x
    x = 335,111.74/721.04
  6. Step 6: Final answer
    x = 464.76

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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.