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Finding the Fourth Proportional to 316.80, 434.39 and 285.59

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Solution

The fourth proportional to 316.80, 434.39 and 285.59 is: 391.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    316.80 : 434.39 = 285.59 : x
  2. Step 2: Convert to fraction form
    316.80/434.39 = 285.59/x
  3. Step 3: Cross multiply
    316.80x = 434.39 × 285.59
  4. Step 4: Simplify right side
    316.80x = 124,057.10
  5. Step 5: Solve for x
    x = 124,057.10/316.80
  6. Step 6: Final answer
    x = 391.59

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.