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Finding the Fourth Proportional to 210.20, 315.45 and 118.80

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Solution

The fourth proportional to 210.20, 315.45 and 118.80 is: 178.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.20 : 315.45 = 118.80 : x
  2. Step 2: Convert to fraction form
    210.20/315.45 = 118.80/x
  3. Step 3: Cross multiply
    210.20x = 315.45 × 118.80
  4. Step 4: Simplify right side
    210.20x = 37,475.46
  5. Step 5: Solve for x
    x = 37,475.46/210.20
  6. Step 6: Final answer
    x = 178.29

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.