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Finding the Fourth Proportional to 280.89, 388.26 and 215.69

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Solution

The fourth proportional to 280.89, 388.26 and 215.69 is: 298.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.89 : 388.26 = 215.69 : x
  2. Step 2: Convert to fraction form
    280.89/388.26 = 215.69/x
  3. Step 3: Cross multiply
    280.89x = 388.26 × 215.69
  4. Step 4: Simplify right side
    280.89x = 83,741.86
  5. Step 5: Solve for x
    x = 83,741.86/280.89
  6. Step 6: Final answer
    x = 298.13

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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.