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Finding the Fourth Proportional to 720.23, 1,080.12 and 309.35

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Solution

The fourth proportional to 720.23, 1,080.12 and 309.35 is: 463.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.23 : 1,080.12 = 309.35 : x
  2. Step 2: Convert to fraction form
    720.23/1,080.12 = 309.35/x
  3. Step 3: Cross multiply
    720.23x = 1,080.12 × 309.35
  4. Step 4: Simplify right side
    720.23x = 334,135.12
  5. Step 5: Solve for x
    x = 334,135.12/720.23
  6. Step 6: Final answer
    x = 463.93

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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.