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Finding the Fourth Proportional to 561.79, 840.82 and 311.25

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Solution

The fourth proportional to 561.79, 840.82 and 311.25 is: 465.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.79 : 840.82 = 311.25 : x
  2. Step 2: Convert to fraction form
    561.79/840.82 = 311.25/x
  3. Step 3: Cross multiply
    561.79x = 840.82 × 311.25
  4. Step 4: Simplify right side
    561.79x = 261,701.02
  5. Step 5: Solve for x
    x = 261,701.02/561.79
  6. Step 6: Final answer
    x = 465.84

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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.