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Finding the Fourth Proportional to 561.13, 840.78 and 286.84

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Solution

The fourth proportional to 561.13, 840.78 and 286.84 is: 429.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.13 : 840.78 = 286.84 : x
  2. Step 2: Convert to fraction form
    561.13/840.78 = 286.84/x
  3. Step 3: Cross multiply
    561.13x = 840.78 × 286.84
  4. Step 4: Simplify right side
    561.13x = 241,169.34
  5. Step 5: Solve for x
    x = 241,169.34/561.13
  6. Step 6: Final answer
    x = 429.79

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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.