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Finding the Fourth Proportional to 389.72, 537.78 and 242.40

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Solution

The fourth proportional to 389.72, 537.78 and 242.40 is: 334.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.72 : 537.78 = 242.40 : x
  2. Step 2: Convert to fraction form
    389.72/537.78 = 242.40/x
  3. Step 3: Cross multiply
    389.72x = 537.78 × 242.40
  4. Step 4: Simplify right side
    389.72x = 130,357.87
  5. Step 5: Solve for x
    x = 130,357.87/389.72
  6. Step 6: Final answer
    x = 334.49

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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.