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Finding the Fourth Proportional to 611.40, 843.60 and 345.78

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Solution

The fourth proportional to 611.40, 843.60 and 345.78 is: 477.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.40 : 843.60 = 345.78 : x
  2. Step 2: Convert to fraction form
    611.40/843.60 = 345.78/x
  3. Step 3: Cross multiply
    611.40x = 843.60 × 345.78
  4. Step 4: Simplify right side
    611.40x = 291,700.01
  5. Step 5: Solve for x
    x = 291,700.01/611.40
  6. Step 6: Final answer
    x = 477.10

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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.