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Finding the Fourth Proportional to 720.51, 1,079.86 and 309.16

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Solution

The fourth proportional to 720.51, 1,079.86 and 309.16 is: 463.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.51 : 1,079.86 = 309.16 : x
  2. Step 2: Convert to fraction form
    720.51/1,079.86 = 309.16/x
  3. Step 3: Cross multiply
    720.51x = 1,079.86 × 309.16
  4. Step 4: Simplify right side
    720.51x = 333,849.52
  5. Step 5: Solve for x
    x = 333,849.52/720.51
  6. Step 6: Final answer
    x = 463.35

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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.