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Finding the Fourth Proportional to 280.29, 387 and 215.22

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Solution

The fourth proportional to 280.29, 387 and 215.22 is: 297.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.29 : 387 = 215.22 : x
  2. Step 2: Convert to fraction form
    280.29/387 = 215.22/x
  3. Step 3: Cross multiply
    280.29x = 387 × 215.22
  4. Step 4: Simplify right side
    280.29x = 83,290.14
  5. Step 5: Solve for x
    x = 83,290.14/280.29
  6. Step 6: Final answer
    x = 297.16

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.