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Finding the Fourth Proportional to 378.70, 522.60 and 210.65

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Solution

The fourth proportional to 378.70, 522.60 and 210.65 is: 290.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.70 : 522.60 = 210.65 : x
  2. Step 2: Convert to fraction form
    378.70/522.60 = 210.65/x
  3. Step 3: Cross multiply
    378.70x = 522.60 × 210.65
  4. Step 4: Simplify right side
    378.70x = 110,085.69
  5. Step 5: Solve for x
    x = 110,085.69/378.70
  6. Step 6: Final answer
    x = 290.70

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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.