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Finding the Fourth Proportional to 720.91, 1,081.37 and 288.07

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Solution

The fourth proportional to 720.91, 1,081.37 and 288.07 is: 432.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.91 : 1,081.37 = 288.07 : x
  2. Step 2: Convert to fraction form
    720.91/1,081.37 = 288.07/x
  3. Step 3: Cross multiply
    720.91x = 1,081.37 × 288.07
  4. Step 4: Simplify right side
    720.91x = 311,506.11
  5. Step 5: Solve for x
    x = 311,506.11/720.91
  6. Step 6: Final answer
    x = 432.10

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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.