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Finding the Fourth Proportional to 390.42, 538.89 and 242.97

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Solution

The fourth proportional to 390.42, 538.89 and 242.97 is: 335.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.42 : 538.89 = 242.97 : x
  2. Step 2: Convert to fraction form
    390.42/538.89 = 242.97/x
  3. Step 3: Cross multiply
    390.42x = 538.89 × 242.97
  4. Step 4: Simplify right side
    390.42x = 130,934.10
  5. Step 5: Solve for x
    x = 130,934.10/390.42
  6. Step 6: Final answer
    x = 335.37

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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.