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Finding the Fourth Proportional to 421.65, 631.65 and 371.70

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Solution

The fourth proportional to 421.65, 631.65 and 371.70 is: 556.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.65 : 631.65 = 371.70 : x
  2. Step 2: Convert to fraction form
    421.65/631.65 = 371.70/x
  3. Step 3: Cross multiply
    421.65x = 631.65 × 371.70
  4. Step 4: Simplify right side
    421.65x = 234,784.31
  5. Step 5: Solve for x
    x = 234,784.31/421.65
  6. Step 6: Final answer
    x = 556.82

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.