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Finding the Fourth Proportional to 281.40, 387.90 and 210.38

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Solution

The fourth proportional to 281.40, 387.90 and 210.38 is: 290.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.40 : 387.90 = 210.38 : x
  2. Step 2: Convert to fraction form
    281.40/387.90 = 210.38/x
  3. Step 3: Cross multiply
    281.40x = 387.90 × 210.38
  4. Step 4: Simplify right side
    281.40x = 81,606.40
  5. Step 5: Solve for x
    x = 81,606.40/281.40
  6. Step 6: Final answer
    x = 290.00

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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.