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Finding the Fourth Proportional to 561.48, 774.84 and 312.79

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Solution

The fourth proportional to 561.48, 774.84 and 312.79 is: 431.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    561.48 : 774.84 = 312.79 : x
  2. Step 2: Convert to fraction form
    561.48/774.84 = 312.79/x
  3. Step 3: Cross multiply
    561.48x = 774.84 × 312.79
  4. Step 4: Simplify right side
    561.48x = 242,360.64
  5. Step 5: Solve for x
    x = 242,360.64/561.48
  6. Step 6: Final answer
    x = 431.65

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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.