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Finding the Fourth Proportional to 315.80, 435.44 and 289.34

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Solution

The fourth proportional to 315.80, 435.44 and 289.34 is: 398.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.80 : 435.44 = 289.34 : x
  2. Step 2: Convert to fraction form
    315.80/435.44 = 289.34/x
  3. Step 3: Cross multiply
    315.80x = 435.44 × 289.34
  4. Step 4: Simplify right side
    315.80x = 125,990.21
  5. Step 5: Solve for x
    x = 125,990.21/315.80
  6. Step 6: Final answer
    x = 398.96

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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.