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Finding the Fourth Proportional to 210.30, 315.50 and 123.70

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Solution

The fourth proportional to 210.30, 315.50 and 123.70 is: 185.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.30 : 315.50 = 123.70 : x
  2. Step 2: Convert to fraction form
    210.30/315.50 = 123.70/x
  3. Step 3: Cross multiply
    210.30x = 315.50 × 123.70
  4. Step 4: Simplify right side
    210.30x = 39,028.14
  5. Step 5: Solve for x
    x = 39,028.14/210.30
  6. Step 6: Final answer
    x = 185.59

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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.