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Finding the Fourth Proportional to 210.08, 315.04 and 86.72

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Solution

The fourth proportional to 210.08, 315.04 and 86.72 is: 130.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.08 : 315.04 = 86.72 : x
  2. Step 2: Convert to fraction form
    210.08/315.04 = 86.72/x
  3. Step 3: Cross multiply
    210.08x = 315.04 × 86.72
  4. Step 4: Simplify right side
    210.08x = 27,320.27
  5. Step 5: Solve for x
    x = 27,320.27/210.08
  6. Step 6: Final answer
    x = 130.05

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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.