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Finding the Fourth Proportional to 275.54, 380.30 and 210.20

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Solution

The fourth proportional to 275.54, 380.30 and 210.20 is: 290.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    275.54 : 380.30 = 210.20 : x
  2. Step 2: Convert to fraction form
    275.54/380.30 = 210.20/x
  3. Step 3: Cross multiply
    275.54x = 380.30 × 210.20
  4. Step 4: Simplify right side
    275.54x = 79,936.11
  5. Step 5: Solve for x
    x = 79,936.11/275.54
  6. Step 6: Final answer
    x = 290.11

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.