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Finding the Fourth Proportional to 720.09, 1,079.42 and 309.02

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Solution

The fourth proportional to 720.09, 1,079.42 and 309.02 is: 463.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.09 : 1,079.42 = 309.02 : x
  2. Step 2: Convert to fraction form
    720.09/1,079.42 = 309.02/x
  3. Step 3: Cross multiply
    720.09x = 1,079.42 × 309.02
  4. Step 4: Simplify right side
    720.09x = 333,555.43
  5. Step 5: Solve for x
    x = 333,555.43/720.09
  6. Step 6: Final answer
    x = 463.21

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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.