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Finding the Fourth Proportional to 720.49, 1,079.94 and 309.91

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Solution

The fourth proportional to 720.49, 1,079.94 and 309.91 is: 464.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.49 : 1,079.94 = 309.91 : x
  2. Step 2: Convert to fraction form
    720.49/1,079.94 = 309.91/x
  3. Step 3: Cross multiply
    720.49x = 1,079.94 × 309.91
  4. Step 4: Simplify right side
    720.49x = 334,684.21
  5. Step 5: Solve for x
    x = 334,684.21/720.49
  6. Step 6: Final answer
    x = 464.52

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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.