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Finding the Fourth Proportional to 210.65, 315.78 and 102.30

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Solution

The fourth proportional to 210.65, 315.78 and 102.30 is: 153.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.65 : 315.78 = 102.30 : x
  2. Step 2: Convert to fraction form
    210.65/315.78 = 102.30/x
  3. Step 3: Cross multiply
    210.65x = 315.78 × 102.30
  4. Step 4: Simplify right side
    210.65x = 32,304.29
  5. Step 5: Solve for x
    x = 32,304.29/210.65
  6. Step 6: Final answer
    x = 153.36

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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.