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Finding the Fourth Proportional to 211.40, 315.40 and 188.30

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Solution

The fourth proportional to 211.40, 315.40 and 188.30 is: 280.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    211.40 : 315.40 = 188.30 : x
  2. Step 2: Convert to fraction form
    211.40/315.40 = 188.30/x
  3. Step 3: Cross multiply
    211.40x = 315.40 × 188.30
  4. Step 4: Simplify right side
    211.40x = 59,389.82
  5. Step 5: Solve for x
    x = 59,389.82/211.40
  6. Step 6: Final answer
    x = 280.94

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.