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Finding the Fourth Proportional to 315.09, 434.40 and 210.20

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Solution

The fourth proportional to 315.09, 434.40 and 210.20 is: 289.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.09 : 434.40 = 210.20 : x
  2. Step 2: Convert to fraction form
    315.09/434.40 = 210.20/x
  3. Step 3: Cross multiply
    315.09x = 434.40 × 210.20
  4. Step 4: Simplify right side
    315.09x = 91,307.92
  5. Step 5: Solve for x
    x = 91,307.92/315.09
  6. Step 6: Final answer
    x = 289.78

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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.