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Finding the Fourth Proportional to 210.48, 315.39 and 138.18

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Solution

The fourth proportional to 210.48, 315.39 and 138.18 is: 207.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.48 : 315.39 = 138.18 : x
  2. Step 2: Convert to fraction form
    210.48/315.39 = 138.18/x
  3. Step 3: Cross multiply
    210.48x = 315.39 × 138.18
  4. Step 4: Simplify right side
    210.48x = 43,580.59
  5. Step 5: Solve for x
    x = 43,580.59/210.48
  6. Step 6: Final answer
    x = 207.05

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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.