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Finding the Fourth Proportional to 405.21, 607.50 and 209.82

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Solution

The fourth proportional to 405.21, 607.50 and 209.82 is: 314.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.21 : 607.50 = 209.82 : x
  2. Step 2: Convert to fraction form
    405.21/607.50 = 209.82/x
  3. Step 3: Cross multiply
    405.21x = 607.50 × 209.82
  4. Step 4: Simplify right side
    405.21x = 127,465.65
  5. Step 5: Solve for x
    x = 127,465.65/405.21
  6. Step 6: Final answer
    x = 314.57

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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.