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Finding the Fourth Proportional to 281.80, 388.76 and 215.38

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Solution

The fourth proportional to 281.80, 388.76 and 215.38 is: 297.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.80 : 388.76 = 215.38 : x
  2. Step 2: Convert to fraction form
    281.80/388.76 = 215.38/x
  3. Step 3: Cross multiply
    281.80x = 388.76 × 215.38
  4. Step 4: Simplify right side
    281.80x = 83,731.13
  5. Step 5: Solve for x
    x = 83,731.13/281.80
  6. Step 6: Final answer
    x = 297.13

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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.